Methods, devices, and systems related to analyte monitoring

ABSTRACT

Generally, methods, devices, and systems related to analyte monitoring and data logging are provided—e.g., as related to in vivo analyte monitoring devices and systems. In some aspects, methods, devices, and systems are provided that relate to enable related settings based on an expected use of an in vivo positioned sensor; logging or otherwise recording analyte levels acquired or derived—e.g., sample analyte levels more frequently than they are logged or otherwise recorded in memory; dynamically adjust the data logging frequency; randomly determine times of acquiring or storing analyte levels from the in-vivo positioned analyte sensors; and enable recording related settings when the system is operable.

CROSS-REFERENCE TO RELATED APPLICATIONS

The present application is a continuation of U.S. patent applicationSer. No. 17/073,589, filed Oct. 19, 2020, which is a continuation ofU.S. patent application Ser. No. 15/868,890, filed Jan. 11, 2018, NowU.S. Pat. No. 10,806,382, which is a continuation of U.S. patentapplication Ser. No. 14/092,035, filed Nov. 27, 2013, now U.S. Pat. No.9,872,641, which claims the benefit of U.S. Provisional Application No.61/731,316, filed Nov. 29, 2012, all of which are incorporated herein byreference in their entirety for all purposes.

BACKGROUND

In many instances it is desirable or necessary to regularly monitor theconcentration of particular constituents in a fluid. A number of systemsare available that analyze the constituents of bodily fluids such asblood, urine and saliva. Diagnosis and management of subjects (e.g.,patients) suffering from diabetes mellitus, a disorder of the pancreaswhere insufficient production of insulin prevents normal regulation ofblood sugar levels, requires carefully monitoring of blood glucoselevels on a daily basis.

In vivo analyte monitoring systems include an in vivo positioned analytesensor. At least a portion of the sensor is positioned beneath the skinsurface of a user to contact bodily fluid (e.g., blood or interstitialfluid (ISF)) to monitor one or more analytes in the fluid over a periodof time. The sensor remains positioned in the user for a period of timeand automatically measures an analyte in the bodily fluid. Data receivedor otherwise derived from analyte monitoring may be communicated toanother device for further processing.

SUMMARY

In some aspects of the present disclosure, the methods, devices, andsystems relate to in vivo analyte monitoring devices and systems, and/orcommunication of data derived therefrom. In vivo analyte monitoringsystems include an in vivo positioned analyte sensor. At least a portionof the sensor is positioned beneath the skin surface of a user tocontact bodily fluid (e.g., blood or interstitial fluid (ISF)) tomonitor one or more analytes in the fluid over a period of time. Dataderived from the in vivo analyte sensor may be transferred or otherwisecommunicated within or between devices—e.g., for logging the data inmemory, processing, etc. For example, a system may include an in vivoanalyte sensor, a sensor electronics unit that has electrical contactsthat electrically and physically connects to the electrical contact(s)of the sensor when the sensor is positioned in vivo (referred to as anon body unit, sensor control unit, and the like), and another (second)electronics device (referred to as an analyte monitoring device, remote,reader, and the like) that communicates with the sensor electronics unitwirelessly. One or both of the sensor electronics unit and/or the(second) electronics device may also communicate wirelessly or with awire to a PC or other processing device.

In some aspects, the system is configurable to switch between aplurality of different modes or configurations, in many instancesautomatically (i.e., passively) without user intervention. For example,the second electronics device may be a universal reader that can beconfigured for a variety of different uses or modes. Configuration maybe accomplished simply by pairing the universal reader to the on bodyunit. This may include transferring configuration information orinstructions between the on body unit and the universal reader, in manyinstances without the user doing anything other than pairing (e.g.,initiating the pairing by bringing the devices in appropriate proximityto each other or other pairing action).

In some aspects of the present disclosure, methods, devices, and systemsare provided that enable configuration settings (e.g., related to userinterface features, or other device settings) of the second electronicsdevice to be settable by the on body unit and the particular desired useof the on body unit. The on body electronics unit can switch between atleast two different settings or uses, and the given setting can bedetermined by the on body unit and communicated to the secondelectronics device. For example, in one embodiment, one type of useprovides for the second electronics device to be configured to operatein a masked mode (e.g., a mode where the analyte levels are notdisplayed or otherwise communicated on the display of the secondelectronics device for the subject to view or otherwise receive), and asecond type of use provides for the second electronics unit to beconfigured to operate in an unmasked mode (e.g., a mode where theanalyte levels are displayed or otherwise communicated on the display ofthe second electronics device for the subject to view or otherwisereceive). In general, the masked mode of operation is particularlyuseful during clinical use (e.g., collecting analyte levels for a periodof time for subsequent analysis by a clinical professional, such as adoctor, for purposes of diagnosis and/or analysis of development ofdisease condition, such as diabetes) of the analyte sensor while theunmasked more of operation is particularly useful during personal use ofthe analyte sensor (e.g., routine, such as daily, monitoring of analytelevels by a user for purposes of controlling a disease condition, suchas monitoring of glucose levels by a diabetic user and optionallyadministering insulin in response to detected glucose levels). Theclinical sensor and the personal use sensor may also include otherconfiguration settings that differ, in addition to or instead of maskedmode and unmasked mode.

In some aspects of the present disclosure, methods, devices, and systemsare provided that sample analyte levels more frequently than they arelogged or otherwise recorded in memory. For example, analyte levelsderived from an in vivo positioned analyte sensor may be recorded atlonger recording intervals than the maximum sampling intervals of thesystem (or recorded at a slower recording frequency than the minimumsampling frequency of the system). If a sampled analyte level to berecorded is missing or contains data that is determined to be not valid,then an alternative sampled analyte level (e.g., a neighboring sampledanalyte level) may be recorded instead if valid—e.g., with anappropriate adjustment to the timestamp of the record. Multiplealternative samples may be selected until a valid sample is found, oruntil a predetermined time to stop is reached.

In some aspects of the present disclosure, methods, devices, and systemsare provided that enable an on body unit (e.g., that includes an in-vivopositioned analyte sensor and sensor electronics coupled to the in-vivopositioned analyte sensor) to dynamically adjust the data loggingfrequency independent of instructions from a second electronics device.For example, in one embodiment, analyte levels are monitored at onefrequency and logged or otherwise recorded in memory at a variablefrequency—e.g., to track the history of the analyte levels. The variablefrequency is adjustable based on the monitored data, and is adjustableto slower frequencies than the frequency at which the monitored data isobtained. Adjusting can be automatic and in real time.

In some aspects of the present disclosure, methods, devices, and systemsare provided that enable an on body unit (e.g., that includes an in-vivopositioned analyte sensor and sensor electronics coupled to the in-vivopositioned analyte sensor) to dynamically adjust the data loggingfrequency based upon communications with a second electronics device,such as analyte monitoring device. The second electronics device maycommunicate frequency-adjusting information to the on body unit that isthen used to determine whether to adjust the variable frequency of therecorded data. The communication of the information and/or theadjustments of the recording frequency may occur at discrete times orotherwise be performed dynamically in real-time, automatically, forexample.

In some aspects of the present disclosure, methods, devices, and systemsare provided that provide for monitoring analyte levels with an in-vivopositioned analyte sensors by acquiring or storing analyte levels fromthe in-vivo positioned analyte sensor at randomly determined periods oftime.

In some aspects of the present disclosure, methods, devices, and systemsare provided that enable the configuration of recording parameters asthe system is being used or otherwise operated. The recording parametersmay include, for example, the recording duration (e.g., the duration oftime that data points should be sampled and stored), the recording rate(e.g., the intervals between recorded samples), etc. For example, asystem designer and/or a user (e.g., a physician, health care provider,patient, etc.) may configure the recording parameters as the system isoperable, for example at least until manufacturing time. In this way,for example, on body unit may be designed with a modest amount of memoryand the system designer and/or user may make the best use of theavailable memory already implemented in the device.

BRIEF DESCRIPTION OF THE DRAWINGS

A detailed description of various embodiments of the present disclosureis provided herein with reference to the accompanying drawings, whichare briefly described below. The drawings are illustrative and are notnecessarily drawn to scale. The drawings illustrate various embodimentsof the present disclosure and may illustrate one or more embodiment(s)or example(s) of the present disclosure in whole or in part. A referencenumeral, letter, and/or symbol used in one drawing to refer to aparticular element may be used in another drawing to refer to a likeelement.

FIG. 1 illustrates a flowchart for configuring and operating an analytemonitoring device with analyte sensing device of different uses,according to one embodiment.

FIG. 2 illustrates a time plot of the sampling and recording of analytelevel data, according to one embodiment.

FIG. 3 illustrates a flowchart for sampling and recording analytelevels, according to one embodiment.

FIG. 4 illustrates a flowchart for sampling and recording analytelevels, according to one embodiment.

FIG. 5 illustrates a flowchart for logging or otherwise recording dataat a variable frequency, according to one embodiment.

FIG. 6 illustrates a flowchart for logging or otherwise recording dataat a variable frequency, according to one embodiment.

FIG. 7 illustrates a flowchart for randomly acquiring analyte levelsfrom an in-vivo positioned analyte sensor for subsequent analysis,according to one embodiment.

FIG. 8 illustrates a flowchart for a method of providing therapeuticrecommendations based on randomly acquired analyte levels derived froman in-vivo positioned analyte sensor.

FIG. 9 illustrates a plot of randomly acquired glucose levels derivedfrom an in-vivo positioned glucose sensor, according to one embodiment.

FIG. 10 illustrates a flowchart for configuring sensor electronics tooperate at a calculated sampling rate, according to certain embodiments.

FIG. 11 shows an analyte monitoring system, according to one embodiment.

FIG. 12 is a block diagram of the data processing unit shown in FIG. 11,according to one embodiment.

FIG. 13 is a block diagram of an embodiment of a receiver/monitor unitsuch as the primary receiver unit of the analyte monitoring system shownin FIG. 11, according to one embodiment.

DETAILED DESCRIPTION

Before the embodiments of the present disclosure are described, it is tobe understood that the present disclosure is not limited to particularembodiments described, as such may, of course, vary. It is also to beunderstood that the terminology used herein is for the purpose ofdescribing particular embodiments only, and is not intended to belimiting, since the scope of the embodiments of the present disclosurewill be limited only by the appended claims.

Where a range of values is provided, it is understood that eachintervening value, to the tenth of the unit of the lower limit unlessthe context clearly dictates otherwise, between the upper and lowerlimits of that range is also specifically disclosed. Each smaller rangebetween any stated value or intervening value in a stated range and anyother stated or intervening value in that stated range is encompassedwithin the present disclosure. The upper and lower limits of thesesmaller ranges may independently be included or excluded in the range,and each range where either, neither or both limits are included in thesmaller ranges is also encompassed within the present disclosure,subject to any specifically excluded limit in the stated range. Wherethe stated range includes one or both of the limits, ranges excludingeither or both of those included limits are also included in the presentdisclosure.

In the description of the present disclosure herein, it will beunderstood that a word appearing in the singular encompasses its pluralcounterpart, and a word appearing in the plural encompasses its singularcounterpart, unless implicitly or explicitly understood or statedotherwise. Merely by way of example, reference to “an” or “the”“analyte” encompasses a single analyte, as well as a combination and/ormixture of two or more different analytes, reference to “a” or “the”“concentration value” encompasses a single concentration value, as wellas two or more concentration values, and the like, unless implicitly orexplicitly understood or stated otherwise. Further, it will beunderstood that for any given component described herein, any of thepossible candidates or alternatives listed for that component, maygenerally be used individually or in combination with one another,unless implicitly or explicitly understood or stated otherwise.Additionally, it will be understood that any list of such candidates oralternatives, is merely illustrative, not limiting, unless implicitly orexplicitly understood or stated otherwise.

Various terms are described below to facilitate an understanding of thepresent disclosure. It will be understood that a correspondingdescription of these various terms applies to corresponding linguisticor grammatical variations or forms of these various terms. It will alsobe understood that the present disclosure is not limited to theterminology used herein, or the descriptions thereof, for thedescription of particular embodiments. Merely by way of example, thepresent disclosure is not limited to particular analytes, bodily ortissue fluids, blood or capillary blood, or sensor constructs or usages,unless implicitly or explicitly understood or stated otherwise, as suchmay vary. The publications discussed herein are provided solely fortheir disclosure prior to the filing date of the application. Nothingherein is to be construed as an admission that the embodiments of thepresent disclosure are not entitled to antedate such publication byvirtue of prior invention. Further, the dates of publication providedmay be different from the actual publication dates which may need to beindependently confirmed.

The term “processor” is used broadly herein, and may include any type ofprogrammable or non-programmable processing device, such as amicroprocessor, microcontroller, application-specific integratedcircuits (ASICS), programmable logic devices (PLDs), field-programmablegate arrays (FPGAs), etc. The term “processor” may also include multipleprocessing devices working in conjunction with one another.

Configuring Settings Based on Use of an Analyte Sensor:

Embodiments of the present disclosure includes a transcutaneouslypositionable analyte sensor in signal communication with electronicswhich process signals from the analyte sensor transfer or otherwiseprovide the processed signals related to monitored analyte level to areceiver unit, a blood glucose meter or other devices configured toreceive, process, analyze, output, display and/or store the processedsignals. Embodiments of the analyte monitoring systems include in vivoanalyte sensors in fluid contact with body fluid such as interstitialfluid to monitor the analyte level such as glucose. Embodiments includeelectronics and/or data processing, storage and/or communicationcomponents that are electrically coupled to the analyte sensor, and mayinclude a housing that is placed or positioned on the body surface suchas on the skin surface and adhered thereon with an adhesive and retainedand maintained in the adhered position for the duration of the analytemonitoring time period using the analyte sensor such as, for example,about 15 days or more, about 10 days or more, about 7 days or more, orabout 5 days or more, or about 3 days or more. The housing including theelectronics and/or data processing, storage and/or data communicationcomponents may be positioned on discrete on-body locations includingunder clothing during the duration of the monitoring time period. Theanalyte monitoring device that is coupled to the body and includes thetranscutaneously positionable analyte sensor, housing, and electronicsand/or data processing, storage and/or communication components, is alsoreferred to herein as an “on-body unit”, “obu”, “on body patch”, or“patch”.

The sensor control unit can be integrated in the sensor, part or all ofwhich is subcutaneously implanted or it can be configured to be placedon the skin of a patient. The sensor control unit is optionally formedin a shape that is comfortable to the patient and which may permitconcealment, for example, under a patient's clothing. The thigh, leg,upper arm, shoulder, or abdomen are convenient parts of the patient'sbody for placement of the sensor control unit to maintain concealment.However, the sensor control unit may be positioned on other portions ofthe patient's body. One embodiment of the sensor control unit has athin, oval shape to enhance concealment. However, other shapes and sizesmay be used.

The particular profile, as well as the height, width, length, weight,and volume of the sensor control unit may vary and depends, at least inpart, on the components and associated functions included in the sensorcontrol unit. In general, the sensor control unit includes a housingtypically formed as a single integral unit that rests on the skin of thepatient. The housing typically contains most or all of the electroniccomponents of the sensor control unit.

When positioned on the skin of a patient, the sensor and the electroniccomponents within the sensor control unit are coupled via conductivecontacts. The one or more working electrodes, counter electrode, andoptional temperature probe are attached to individual conductivecontacts. For example, the conductive contacts are provided on theinterior of the sensor control unit. Other embodiments of the sensorcontrol unit have the conductive contacts disposed on the exterior ofthe housing. The placement of the conductive contacts is such that theyare in contact with the contact pads on the sensor when the sensor isproperly positioned within the sensor control unit.

The sensor control unit also typically includes at least a portion ofthe electronic components that measure the sensor current and theanalyte monitoring device system. The electronic components of thesensor control unit typically include a power supply for operating thesensor control unit, a sensor circuit for obtaining signals from thesensor, a measurement circuit that converts sensor signals to a desiredformat, and a processing circuit that, at minimum, obtains signals fromthe sensor circuit and/or measurement circuit and provides the signalsto an optional transmitter. In some embodiments, the processing circuitmay also partially or completely evaluate the signals from the sensorand convey the resulting data to the optional transmitter and/oractivate an optional alarm system if the analyte level exceeds athreshold. The processing circuit often includes digital logiccircuitry.

The sensor control unit may optionally contain a transmitter fortransmitting the sensor signals or processed data from the processingcircuit to a receiver/display unit; a data storage unit for temporarilyor permanently storing data from the processing circuit; a temperatureprobe circuit for receiving signals from and operating a temperatureprobe; a reference voltage generator for providing a reference voltagefor comparison with sensor-generated signals; and/or a watchdog circuitthat monitors the operation of the electronic components in the sensorcontrol unit.

In vivo analyte monitoring devices and system may include an on bodyunit having sensor electronics and an analyte sensor whereby at least aportion of the sensor is positioned beneath the skin surface of a userto contact bodily fluid (e.g., blood or interstitial fluid (ISF)) tomonitor one or more analytes in the fluid over a period of time. In someembodiments, the analyte levels are communicated to a second electronicsdevice, such as an analyte monitoring device, which remains in constant(e.g., continual, continuous) signal communication range with the onbody unit thereby transferring the analyte levels to the analytemonitoring device at continuous or near continual rate.

In other embodiments, the analyte levels are communicated to secondelectronics device, such as an analyte monitoring device, only when theanalyte monitoring device is brought into signal communication rangewith the on body unit. For example, the signal communication can beconfigured for only near field communication, such as, for example,through RFID protocol and the like. Such an exemplary in vivo measuringembodiment provides for collection of analyte data from the on bodysensor upon demand (i.e., flash) by the user upon bringing the analytemonitoring device in close proximity to the on body unit such that theyare in signal communication with one another to transfer the analyteinformation and then taken out of signal communication range of oneanother. In addition, such embodiments are optionally also configured toprovide for no user calibration of the analyte levels derived from thein vivo sensor by using, for example, blood glucose derived analytelevels (e.g., capillary blood from a finger, arm, palm, etc.) using anin vitro blood glucose test strip and meter.

In some aspects of the present disclosure, the configuration settings(e.g., related to user interface features or settings) of the analytemonitoring device are determined by the on body unit and/or its use. Insome embodiments, the analyte monitoring device is configurable tooperate with on body units of different uses (e.g., masked or blindeddisplay uses, and unmasked or unblinded display uses), which havedifferent analyte monitoring device settings (e.g., user interfacesettings) associated with them. Example settings may include, but arenot limited to: display settings (e.g., whether to display analytelevels on the display of the reader); data sampling and/or loggingfrequency settings (e.g., 5 hours of 10 minute data, 8 hours of 15minute data, 24 hours of 45 minute data, etc.); settings for the life ofthe sensor (e.g., 7 days, 14 days, etc.), user interface settings (e.g.,reminders, statistics, activation of bolus calculator, or other featuresassociated with visual representation of when the sensor analyte valuesmay be accurate enough to enable treatment decisions; report settings,either printed, displayed, or both (e.g., specific reports may beenabled, prioritized, etc. for the corresponding application), etc.These settings may vary depending on the specific use of the on bodyunit. The settings described are exemplary, and other settings may beapplicable in other embodiments.

In one embodiment, the analyte monitoring device is configured based onsensor-use information that is received from the on body unit. Thesensor-use information indicates the type of use that the sensor isconfigured for—e.g., a first use such as masked or blinded (clinicaluse) and at least a second use such as unmasked or unblinded (personaluse). The sensor-use information may be stored in memory of the on bodyunit and communicated to the analyte monitoring device upon initialsignal communication between the two, for example, such asinitialization of the system. Based on the type of use indicated by thesensor-use information, the analyte monitoring device is configuredaccordingly for the indicated use. In one embodiment, the analytemonitoring device is automatically configured by the on body unit. Inanother embodiment, at least user confirmation of the configuration isrequested by one of the system components, and may not proceed with oneor more functions until received. In some embodiments, the user may berequired to perform some other action on one or more of the first andsecond devices such as actively selecting a particular setting fromamongst a plurality of available settings. This may be included on auser inter face of one or more of the devices of a system. Accordingly,configuration may be semi-automatic or less.

The sensor-use information may include, for example, identificationinformation for the on body unit that may be unique to each device, suchas a unique identification (UID), a programmed flag or some otherinformation stored on the on body unit to indicate the desired use. Theanalyte monitoring device may include information stored in memory, forexample, that identifies or otherwise associates each sensor-useinformation with its corresponding use, and further with the associatedsettings for the corresponding use. The analyte monitoring device mayuse the stored information to determine the associated use (e.g., maskedor unmasked) and then initiate the configuration of the analytemonitoring device with the associated settings. For example, in oneembodiment, the unmasked use sensor differs from the masked use sensorin that the unmasked use sensor displays analyte values to the user viathe display on the analyte monitoring device and the masked does not.

For example, a physician or health care provider may provide a subject(e.g., patient) with an analyte monitoring device and on body unitconfigured for masked (clinical) use. For instance, the subject may be adiabetic subject and the glucose sensing device provided in order toobtain a baseline or other view of the subject's glycemic control. Atthis time, the analyte monitoring device is configured with settings forthe masked version of the on body unit—e.g., operating in a clinicalmode that does not display glucose values to the user, etc. Uponcommunication between the clinical use on body unit and the analytemonitoring device (e.g., upon activating the clinical use sensingdevice, or upon performance of a glucose reading if applicable, etc.),the sensor-use information that is stored on the clinical use on bodyunit communicated to the analyte monitoring device, for examplewirelessly by an RF communication protocol such as RFID or the like.Sensor-use information (e.g., sensor unique ID, etc.) indicates to theanalyte monitoring device that the on body unit is a clinical usesensor, and the analyte monitoring device is configured accordingly forthe clinical use settings.

After the subject is finished with the clinical use version of the onbody unit, the same analyte monitoring device may be used as a monitorwith a different on body unit configured for a different use (e.g.,personal use) to monitor glucose levels. An on body unit for unmasked(personal use) may be obtained, and replace the first masked unit. Uponcommunication between the unmasked on body unit and the currentlyconfigured masked analyte monitoring device (e.g., upon activating thepersonal use sensor, or upon performance of a reading, etc.), thesensor-use information that is stored on the new or second unmasked useon body unit is communicated to the currently configured masked analytemonitoring device. The sensor-use information (e.g., sensor UID, etc.)indicates to the analyte monitoring device that the on body unit is anunmasked device, and the analyte monitoring device is then configuredaccordingly to a second or unmasked state to match the masked state ofthe on body unit in current use (e.g., in an unmasked mode that displaysanalyte values to the user).

In one embodiment, the sensor-use information may distinguish betweendifferent types of on body units that are configured for personal usebut that have their own specific settings associated with them. Thesesettings may differ, for example, based on the differences in varioussensors—e.g., differences in models of the sensors, differences in thefirmware or software of the sensors, etc. In some instances, prices forthe unmasked use on body units and the masked use on body units may thenbe decoupled and based upon the features that are unlocked with theirrespective use. Accordingly, based on the personal use on body unitpaired with the analyte monitoring device, all features of themonitoring device may be activated, or certain features may beactivated, while others may be deactivated. Such activating anddeactivated features may include accessibility to logbook features,flagging of analyte values as pre- or post-meal, data analysis such asderiving analyte level pattern information from analyte values over aperiod of days, etc. Furthermore, in the sensor-use information maydistinguish between a battery operated on body unit and a self-poweredon body unit as described in U.S. Patent Application Publication No.2010/0213057, the subject matter of which is incorporated herein byreference in its entirety. In such embodiments, when a self-powered onbody unit is used the analyte monitoring device may be configured toreceive trend information from resistor pairs as described in U.S.Patent Application Publication No. 2011/0257495, the subject matter ofwhich is incorporated herein by reference in its entirety.

In other embodiments, configuration of the analyte monitoring device mayalso be done, for example, via other passive approaches such as barcoding (e.g., on the on body unit, inserter, and/or product labeling),user entry of a key code, and/or through the reader user interface.

FIG. 1 illustrates a flowchart for configuring and operating an analytemonitoring device with on body unit of different uses, according to oneembodiment. At block 1005, when the analyte monitoring device and the onbody unit are communicably coupled, sensor-use information stored in theon body unit is received by the analyte monitoring device.

At block 1010, the analyte monitoring device determines configurationsettings associated with the sensor-use information. For example, theanalyte monitoring device may have specific configuration settings foreach of the different types of sensor-uses, which is indicated by thesensor-use information. The analyte monitoring device may include memorythat contains data that associates the specific sensor-use informationwith their corresponding configuration settings for the analytemonitoring device (e.g., stored in a look-up table in memory of theanalyte monitoring device). In another embodiment, the sensor-useinformation includes the information for the associated settings andprovides the configuration settings to the analyte monitoring device.

If the sensor-use information is associated with a first type ofsensor-use (e.g., clinical use), then the analyte monitoring device isconfigured with settings for the first type of sensor-use and thenoperated with those settings, as represented by block 1030 and 1035,respectively. Alternatively, if the sensor-use information is associatedwith a second type of sensor-use (e.g., personal use), then the analytemonitoring device is configured with settings for the second type ofsensor-use and then operated with those settings, as represented byblock 1020 and 1025, respectively.

The first type of sensor-use (e.g., clinical) and second type ofsensor-use (e.g., personal) may include one or more different settings.In some embodiments, there may be more than two types of sensor-use. Thetypes of sensor-use may have different configuration settings associatedwith them, such as one or more of the following: analyte level displaysettings, such as whether to display analyte levels on the display ofthe reader; data sampling and/or logging frequency settings; settingsfor the life of the sensor, the analyte monitoring device's userinterface settings (e.g., reminders, statistics, activation of boluscalculator, or other features associated with visual representation ofwhen the sensor glucose values may be accurate enough to enabletreatment decisions); report settings, either printed, displayed, orboth (e.g., specific reports may be enabled, prioritized, etc. for thecorresponding application), etc.

In one embodiment, one type of on body unit is clinical use and theother type of on body unit is personal use, where in clinical use theanalyte monitoring device is configured to operate in a masked mode(e.g., a mode where the analyte levels are not displayed on the displayof the analyte monitoring device for the subject to view), and inpersonal use, the analyte monitoring device is configured to operate inan unmasked mode, e.g., a mode where the analyte levels are displayed onthe display of the analyte monitoring device for the subject to view.The clinical sensor and the personal use sensor may also include otherconfiguration settings that differ, in addition to masked mode andunmasked mode.

Selective Data Logging:

Analyte levels acquired by analyte sensors at a constant recordingfrequency (e.g., every 10 minutes) are affected by noisy or otherwiseinaccurate data, such as transient signals for instance. When therecording frequency is low, transient signal faults that coincide withscheduled recording times may significantly impact the quality of therecorded data. For example, if a normal signal contains an unwanteddisturbance at time t that lasts for one minute, a system with aone-minute recording frequency would log one time point of faulty data,bracketed by normal (“valid”) data points both one minute before and oneminute after time t. In this case, the signal disturbance causes atwo-minute gap between valid data points in the log. However, if thesame signal is recorded at longer intervals such as ten minuteintervals, and a recording is made at time t, then the gap between validdata points in the log is much larger—e.g., 20 minutes. Low recordingfrequency can significantly compromise signal processing algorithms(e.g., interpolation between valid logged data points) when transientsignal disturbances are present.

In some aspects of the present disclosure, methods, devices, and systemsare provided that sample analyte levels more frequently than they arelogged or otherwise recorded in memory. For example, analyte levelsderived from an in vivo positioned analyte sensor may be recorded atlonger intervals than the maximum sampling intervals of the system (orrecorded at a slower recording frequency than the minimum samplingfrequency of the system). If a sampled analyte level to be recorded ismissing or contains data that is determined to be not valid, then analternative sampled analyte level (e.g., a neighboring sampled analytelevel) may be recorded instead if valid—e.g., with an appropriateadjustment to the timestamp of the record. In this way, the selectivelydata logging may improve the data inputs available for signal processingand increase the robustness of the sensing system to transient signalfaults. Furthermore, slower recording frequencies may benefit datastorage and data transfer limitations of low cost sensing systems.

The sampling of analyte levels refers generally herein to the analytelevels obtained from the in-vivo positioned sensor. The recording orlogging of the analyte levels refer generally to the storing of analytelevels to memory. The recorded analyte levels may then, for example, beused by signal processing algorithms in the processor of the device oranother device.

In some instances, a valid alternative analyte level may not be found.For example, limits may be placed on how far in to the past and futurethe data logging algorithm will look for a valid alternative sample torecord if the sample at a scheduled recording time point is invalid. Incases where no valid alternative sample can be found, predeterminedcriteria may be used to determine what analyte level is to be recorded,whether no record should be recorded in such case, etc.

The term “valid” is used herein to refer generally to whether a datapoint is determined to be worth recording, or a level of worthiness forrecording. Any variety of algorithms may be implemented and may utilizevarious factors and considerations; however, the algorithms shouldultimately provide a validity determination for a give data point. Insome embodiments, the validity of a data point may be binary (e.g.,either valid or invalid). A valid data point would be consideredacceptable to record and an invalid data point would be consideredunacceptable to record (e.g., a missing analyte level, significantlyunstable or corrupted analyte level (e.g., by noise or transient signalfaults, etc.). In other embodiments, the validity of a data point maynot be binary but rather be a level of validity. For example, variouslevels of validity may be implemented to reflect a data point'sworthiness of being recorded—e.g., as based on a data point's level ofstability, degree of accuracy, or degree of corruption; or on a datapoint's likelihood of being stable, accurate, or uncorrupted; etc.Absent analyte levels would have a low, if not lowest level of validity,for instance.

In some aspects, the methods, devices, and systems relate to devices andsystems including an in-vivo positioned analyte sensor that may beconfigured so that at least a portion thereof is placed under the skinof the subject to detect the analyte levels of the subject, and anotherportion of the analyte sensor—which may be above the skin—is coupled toelectronics within a housing that is positioned externally on the skinof the subject. The sensor electronics may include various components,such as communication element(s) for communication with a remotereceiving unit; a processor; memory; etc.

The terms “on body unit” and “analyte sensing device” are used herein togenerally refer to the entire sensing device including the in-vivopositionable analyte sensor, sensor electronics coupled to the in-vivopositionable sensor (e.g., data processing, storage, and/orcommunication components), and housing which couples to the subject'sbody. The analyte sensing device is configured to communicate (e.g.,wired or wirelessly) with an analyte monitoring device and send analytedata to the analyte monitoring device. The analyte monitoring device maybe, for example, an any variety of hand-held measurement instruments oranalysis instruments, such as a remote or reader for instance. Theanalyte monitoring device may also be another data processing devicesuch as a personal computer, laptop, cell phone or smartphone, personaldigital assistant (PDA), etc. For example, glucose samples may besampled from an in vivo positioned glucose sensor by the sensorelectronics coupled to the in-vivo positioned glucose sensor, andrecorded in memory of the sensor electronics at longer intervals thanthe maximum sampling interval. The recorded glucose levels may then besent to a receiving unit, such as a glucose monitoring device.

In one embodiment, for example, data is recorded at intervals of T_(R)and sampled at intervals of T_(S), which is a multiple of T_(R). If arecording is scheduled at time t, and the sample at time t is invalid,wait until time t+T_(S) to sample. If the sample is valid, then recordthe sample. If it is not valid, then wait to sample at t+2 T_(S), t+3T_(S), . . . , t+nT_(S), stopping when a valid record is found. In oneembodiment, nT_(S) should not exceed T_(R), and n should not exceed apredefined n_(max). The algorithm is not confined to start at time t,and may start as early as t−n_(max)T_(S), and stop as soon as it reachesthe first valid point, for example. A recording window may be usedherein to refer generally an interval of time defined by the recordingtime points immediately prior to and immediately subsequent to a givenrecording time point. For instance, in the example provided, the timeinterval between t−n_(max)T_(S) and t+n_(max)T_(S) may be referred to asthe recording window.

In some embodiments, if the validity of a sample is not a binary (e.g.,valid or invalid) metric but a continuous or discrete value (e.g.,signal stability levels, where 0 is completely unstable and 10 isperfectly stable), the selective data logging algorithm may weigh thevalidity of the sample (e.g., against its deviation from the scheduledrecording time), so that an optimal sample can be recorded for instance.In one embodiment, for example, a penalty function may be defined as afunction of Δt, where Δt is the difference between the scheduledrecording time and any given alternative recording time. The output ofthe penalty function may be combined with the validity metric of a givenalternative recording time to score the samples and identify the optimalsample to record in the data log, for instance.

The methods, devices, and systems may be implemented with or without asample buffer. For example, multiple samples may be stored in atemporary data buffer, and all samples in the buffer may be evaluated todetermine the optimal sample to record. In the absence of a buffer, forexample, the data logging algorithm may start by recording the n_(max)^(th) sample before time t. If the next sample has a better validityscore, then it will replace the existing record with the most recentsample. For instance, the algorithm may only replace the current recordif it finds a sample with a better validity score.

Rather than replacing data records with more valid sample data, in someembodiments, the method may combine data from multiple samples toproduce the values stored in the data record. For example, if all thesamples in the recording window do not meet the validity criteria forrecording, the median of all the sample values (or any subset thereof)may be recorded rather than recording no value at all.

The method, devices and systems, may not be limited to data logging of asingle channel of data, and may include multi-channel data wheretransient signal faults may occur along any (or all) of the datachannels. In the case of multi-channel data, the validity scoringfunctions may depend on several input channels, for example. In someinstances, the scoring functions may be defined differently for eachchannel. In some instances, the optimal record that is ultimately loggedmay contain channel data that is not necessarily form the same timepoint, so that signal faults in any signal channel do not prevent acomplete record from being logged and used in downstream signalprocessing.

In some embodiments, the value of “n” may be recorded along with eachdata sample. In this way, for example, it may be indicated to subsequentsignal processing routines (in the same or different device) whether thedata time was altered, to what degree that the data timing was altered,etc. For example, for a ten minute sample, if n_(max) is 5, then 4additional bits (enough to represent 11 possibilities) may be recordedper data sample. The signal processing routine may use this informationalong with standard interpolation techniques, for example, to estimatewhat the value at the regular sample spacing time is.

FIG. 2 illustrates a time plot of the sampling and recording of analytelevel data, according to one embodiment. Plot 101 shows samplingintervals represented by time points along a timeline. The time pointsdefine intervals of T_(S), also referred to as the sampling interval.The sampling of analyte levels occurs at sampling intervals T_(S),beginning at time point T₁. For example, at time point t₁, an in-vivopositioned sensor is sampled and an analyte level obtained, asrepresented by the data point 145 at t₁. After the sampling interval ofTS, another analyte level is obtained, as represented by the data point140 at time point t1+TS. After another sampling interval, anotheranalyte level is obtained, as represented by the data point 135 at timepoint t1+2TS. Similar data points 130, 150, 155 are shown atcorresponding time points t1+5TS, t1+6Ts, t1+7 TS, respectively. Datapoints 120, 125 are shown as a letter “X” at time points t1+3TS andt1+4TS, respectively, and represent data points with validityconcerns—e.g., missing data, invalid data (e.g., unstable values,corrupted values from noisy or transient signal faults, outliers values,dropouts values, etc.), or data that is otherwise unlikely to be validor considered to have a low validity level.

Plot 102 shows recording intervals defined by recording time pointsalong a timeline. The time points occur at intervals of TR, alsoreferred to as the recording interval. The recording of sampled analytelevels are shown to occur at the recording interval TR, beginning attime point T1. For example, analyte levels are recorded as shown by thedata points 160, 170, 180 at time points t1, t1+TR, T1+2TR,respectively. In the embodiment shown, the recording interval T_(R) is amultiple of T_(S)—more specifically, T_(R) is three times the size ofT_(S). In other embodiments, recording interval T_(R) may be includemore than one sampling interval T_(S). In some instances, T_(R) may beanother multiple of T_(S). Also shown is recording window 115, which isa time interval defined by the recording time points t1 and t1+2TR thatare immediately prior to and immediately subsequent to time point t1+TR,respectively.

The value of the analyte levels recorded for each recording interval aredetermined based on validity determinations performed on one or more ofthe sampled analyte levels, which will be discussed in further detail inFIGS. 2 and 3.

FIG. 3 illustrates a flowchart for sampling and recording analytelevels, according to one embodiment. At block 205, analyte levels aresampled at sampling intervals. For example, an analyte sensor may becoupled to sensor electronics and positioned in-vivo in a subject. Theanalyte sensor may be activated and begin sampling analyte levels atsampling intervals. For example, at each sampling time point of thesampling intervals, an analyte level is obtained or attempted to beobtained. In some case, a valid analyte level is obtained and at othertimes an invalid or otherwise inaccurate analyte level may be obtainedinstead. For example, an analyte level may not be present or may not besufficiently valid for recording (e.g., due to signal noise ordisturbances, transient signals faults, signal outliers, signaldropouts, etc.).

The sampled analyte levels are initially set to be recorded at recordingintervals which are larger than the sampling intervals (e.g., to includemore than one sampling interval, such multiple sampling intervals). Atblock 210, a sampled analyte level at a time point of a recordinginterval is selected, and at block 215 a validity determination isperformed on the selected sample. The sample initially selected forrecording is the sampled analyte level coinciding with the nextrecording time point. For example, referring back to FIG. 1, at timepoint t1, the sampled analyte level 145 is selected. Instead of beingrecorded, sampled analyte level 145 is subjected to a validitydetermination to determine if it is a valid data point. Any variety ofvalidity determination algorithms may be implemented to determine if theanalyte level is a valid analyte level.

If the analyte level is determined to be valid, then the selectedanalyte level is recorded, as represented by block 220, and the processrepeated for the next recording time point, as represented by the arrowfrom block 220 back to block 205. If the analyte level is determined tobe invalid, then an alternative sampled analyte level is selected and avalidity determination performed on the alternative analyte level, asrepresented by blocks 225 and 230, respectively. In the embodimentshown, the alternative sampled analyte level is selected from within therecording window of the initially selected sample that was determined tobe invalid. For example, referring back to the example for FIG. 1, afteranalyte level 145 was recorded for time point t1, the analyte levelsampled at the next recording time point t1+TR is selected. The sampledanalyte level coinciding with the recording time point t1+TR is shown asdata point 120. Data point 120 represents a missing or invalid datapoint, and thus when data point 120 is selected at block and a validitydetermination is performed, an invalid determination results. In suchcase, an alternative sampled analyte level is selected, as representedby block 225.

If the validity determination of the alternative sampled analyte levelis valid, then the alternative sampled analyte level is recorded insteadof the initially selected sampled analyte level at block 210. Theprocess is then repeated for the next recording time point, asrepresented by the arrow from block 235 back to block 205.

For example, if sampled analyte level 135 is selected at block 225 asthe alternative sample, then a validity determination is performed onanalyte level 135 at block 230. As sampled analyte level 135 is shown asa valid data point, the validity determination results in a valid datapoint and then the sampled analyte level 135 is recorded at recordingtime point t1+TR, in place of data point 120 which was determined to beinvalid, as represented by block 235.

If the validity determination of the alternative sampled analyte levelis invalid, then another alternative sampled analyte level may beselected (if permitted) and a validity determination performed on thealternative analyte level, as represented by the flow path from block230 back to block 225). In the embodiment shown in FIG. 2, at block 240,it is determined whether another alternative sampled analyte levelshould be selected.

If, for example, the alternative analyte level selected at block 225 wassampled analyte level 125, then a validity determination is performed onthe analyte level 125 at block 230. As sampled analyte level 125 isshown as an invalid data point, the validity determination results in aninvalid data point. If it is determined at block 240, that anotheralternative sample should be selected, then another alternative sampledanalyte level is selected for validity determination, as represented bythe arrow from block 240 back to block 225.

For example, the device or system may be programmed to stop selectingalternative analyte levels for validity determination according topredetermined criteria—e.g., after a predetermined threshold number ofalternative analyte levels (e.g., after 1 alternative analyte level, or2 alternative analyte levels, or 3 alternative analyte levels, etc.),etc. If, for instance, an invalid determination is found at block 230,then it is determined if the last threshold alternative analyte levelhas been selected and tested for validity, as represented by block 240.If the last threshold alternative analyte level has not been selectedyet, then another alternative analyte level is selected, as representedby the arrow back to block 225. In one embodiment, the system isprogrammed to stop selecting alternative analyte levels before reachingthe sampled analyte level at the end of the recording window (e.g., thesampled analyte level coinciding with the previous and/or next recordingtime point). For example, for recording time point t1+TR, the end of therecording window 115 resides at recording time points t1 and t+2TR. Insuch case, depending on the order of selection, the system would beprogrammed to stop selecting alternative analyte levels before reachingthe sampled analyte levels coinciding at either time point t1 or timepoint t1+6TS, which may be more applicable to the recordings for timepoints t1 and t1+6TS than the recording at time point t1+TR.

If the last threshold alternative analyte level has already beenselected and determined to not be valid, then at block 245 anappropriate measure is taken as predetermined. For example, it may bepredetermined to record no analyte level for the corresponding recordingtime point. Alternatively, the device or system may be programmed torecord a representative analyte level. For instance, the system mayselect one of the selected sampled analyte levels that is determined tobe closest to a valid data point, may average or weight two or moresampled analyte levels at the recording time point (e.g., two or more ofthe samples in the corresponding recording window), may calculate orotherwise generate another representative analyte level, etc. Afterblock 245, the process is continued to determine the analyte level to berecorded at the next recording time point.

The order of selection of alternative analyte levels may vary indifferent embodiments. For example, in one embodiment, each successivelyselected alternative analyte level is the sample at the next subsequentsampling time point—e.g., from time point t1+3TS in FIG. 1, the firstalternative analyte level occurs at the next subsequent sampling timepoint of t1+4TS, the second alternative analyte level occurs at the nextsubsequent sampling time point t1+5TS, etc. In another embodiment, forexample, each successively selected alternative analyte level is thesample at the previous sampling time point (e.g., from time point t1+3TSin FIG. 1, the first alternative analyte level occurs at the previoussampling time point of t1+2TS, the second alternative analyte level (ifit were invalid) would occur at the previous sampling time point t1+1TS,etc. In yet another embodiment, for example, the device or system may beprogrammed to select alternative analyte levels based on distance fromthe recording time point—e.g., from time point t1+3TS in FIG. 1,alternative analyte levels at time points t1+2TS and t1+4S would beselected (in either order) before analyte levels at time points t1+2T1and t1+5TS, etc. In yet other embodiments, other permutations may beimplemented for the order of selection of alternative analyte levels.

In some embodiments, the analyte levels are recorded in memory alongwith adjusted time stamps for alternative analyte levels that wererecorded. For example, referring to FIG. 1, if the sampled analyte level130 at sampling time point t1+5TS is used for recording time pointt1+TR, then an adjusted time stamp (e.g., t1+5TS) is also recorded withthe analyte level 130 to reflect the time of the alternative analytelevel 130.

FIG. 4 illustrates a flowchart for sampling and recording analytelevels, according to one embodiment. At block 305, analyte levels aresampled at sampling intervals. At each sampling time point of thesampling intervals, an analyte level is obtained or attempted to beobtained. Again, in some cases, a valid analyte level is obtained and atother times an invalid analyte level may be obtained instead.

At block 310, a sampled analyte level coinciding with a recording timepoint is selected. At block 315, one or more alternative samples withinthe recording window for the recording time point is selected. Forexample, in one embodiment, two sampled analyte levels may be selected(e.g., the analyte level coinciding with the current recording timepoint and the next subsequent sampled analyte level). In anotherembodiment, for example, three sampled analyte levels may be selected(e.g., the analyte level coinciding with the current recording timepoint, and the immediately preceding and following sampled analytelevels from the current recording time point). Any variety ofcombinations of sampled analyte levels in the recording window may beimplemented in other embodiments.

At block 320, validity metrics are calculated for the sampled analytelevel coinciding at the recording time point and for the one or morealternative sampled analyte levels that were selected at blocks 310 and320. The calculated validity metric may be a number or value used torepresent the degree, level, or score of validity for an analyte level,as determined by any variety of validity determination algorithms. Forexample, the validity metric may be a level from 1 to 5, where 1represents the least amount of assurance of validity and where 5represents the highest assurance of validity. In other embodiments,other scales or numbering systems may be implemented—e.g., 1 to 10; low,medium, high; etc. In this way, the validity determination may includelevels of validity as opposed to a binary (valid or invalid)determination.

At block 325, the validity metrics are weighed based on their timedeviation from the recording time point from block 310. For example, inone embodiment, validity metrics associated with greater deviations fromthe recording time point from block 310 are given less weight thanvalidity metrics that have smaller deviations from the recording timepoint. In this way, the resulting weighted validity metric is a productof both the validity metric (e.g., the level of validity) and theweighting (e.g., the deviation from the recording time point), andaccount for both factors.

At block 330, an analyte level for recording is determined based on theweighted validity metrics for the selected analyte levels. For example,in one embodiment, the resulting weighted validity metric with the mostoptimum value for validity determines which analyte level is selectedfor recording. The process is then repeated as represented by the arrowback to block 305.

In another embodiment, the validity metric may be used without beingweighted (e.g., as shown in block 320), and the sampled analyte levelwith the most optimum validity metric determines which analyte level isrecorded. In other embodiments, other factors may also be used incombination with the weighted validity metric (or the non-weightedvalidity metric) to determine which analyte level is to be recorded. Inother embodiments, the weighted validity metrics (or non-weightedvalidity metrics) are used to calculate or generate a representativeanalyte level for the recording time point.

Adjustable Logging Frequency:

In some aspects, methods, devices, and systems are provided that enablean on body unit (e.g., including an in-vivo positioned analyte sensorand sensor electronics coupled to the in-vivo positioned analyte sensor)to dynamically adjust the data logging frequency independent ofinstructions from the analyte monitoring device (e.g., any variety ofhand-held analyte measurement instruments or analysis instruments, suchas a reader for instance).

In one embodiment, analyte levels are monitored at a faster frequencythan the frequency at which the analyte levels are logged or otherwiserecorded in memory—e.g., to track the history of the analyte levels. Themonitored analyte levels obtained at the faster rate is referred toherein as “fast data”, while the data recorded at the slower andvariable rate is referred to herein as “slow data” or “variable data”.The fast data is used to adjust the variable frequency of the slow data.For example, the slow data may be recorded at different frequenciesbased on the characteristics of the fast data, such as how steady thefast data is, etc. For instance, in one embodiment, when fast data issteady or relatively slow (e.g., having no rate-of-change or smallrate-of-change), the device may record the slow data at a slow frequency(e.g., 10, 20, 30 minutes, etc.), and when the fast data is rapidlychanging (e.g., having a faster rate-of-change), then the device mayrecord the slow data at a faster frequency (e.g., 1, 2, 5 minutes,etc.). The value of a steady or low rate of change may vary in differentembodiments. In some instances, an example of low rates of changes mayinclude, but are not limited to, 2 mg/dL/min or less, such as 1mg/dL/min or less. The value of a high rate of change may vary indifferent embodiments. Example high rates of changes may include, butare not limited to 1 mg/dL/min or greater, such as 2 mg/dL/min orgreater. The low rate of change and high rate of change may be defineddifferently or include additional constraints in other embodiments. Forexample, the definitions and constraints may vary depending on how manydata points are used to determine the rate of change, how long theduration of the rate of change exceeds a threshold, etc.

Various frequencies may be implemented for the slow data and fast datain different embodiments. Further, the frequency at which the slow datais recorded and how it is adjusted based on the fast data may beprogrammed in different manners or based on different criteria. Therate-of-change levels that are used to trigger changes in the variabledata may also be used for other reasons, such as determining analytetrends—e.g., as displayed on the user interface of the reader.

In one embodiment, the monitored analyte levels (or fast data) isequivalent to the sampled analyte levels. In other words, the sampledanalyte levels are monitored. In another embodiment, the monitoredanalyte levels are slower than the sampled analyte levels (e.g., everyother sampled analyte level, every third sampled analyte level, etc.).

In one embodiment, the monitored analyte levels are stored in memorytemporarily to maintain a rolling log for example. The memory may besized to hold enough monitored analyte levels to determine how to adjustthe variable data.

For example, in one embodiment, an on body unit monitoring sampledanalyte levels (e.g., glucose levels) at a specific rate or frequencyand keeps a rolling log for a predetermined period of time. An examplemay include, but is not limited to, sampling analyte levels once everyminute and keeping a rolling log of 16 minutes. The slow data may thenbe used to record or otherwise store sampled analyte levels for a longerduration than the rolling log for the fast data. For example, therolling log for the fast data may be configured for 16 minutes of data,while the memory for the slow data may be able to store data for an8-hour period. These values are exemplary and other values may beimplemented. The slow data recorded may then be sent to a remotereceiving unit, such as an analyte monitoring device (e.g., glucosemeter or reader), when the receiving unit is brought into communicationrange with the on body unit including the in-vivo positioned analytesensor.

FIG. 5 illustrates a flowchart for logging or otherwise recording dataat a variable frequency, according to one embodiment. At block 405,analyte levels derived from an in-vivo positioned sensor are received.For example, sensor electronics coupled to the in-vivo positionedanalyte sensor may receive the analyte level data as they are sampled.The in-vivo positioned sensor may be sampled every minute. The samplingfrequency is exemplary and other sampling frequencies may beimplemented.

At block 410, the sampled analyte levels are monitored at a firstfrequency. In one embodiment, the sampled analyte levels are monitoredat the rate at which they are sampled. For example, the analyte levelsmay be sampled every minute with each sample being monitored. In anotherembodiment, the sampled analyte levels are monitored at a slower ratethan the sampling rate. For example, the analyte levels may be sampledevery minute but monitored every other minute. The values provided areexemplary and other values may be implemented.

At block 415, the sampled analyte levels are logged or otherwiserecorded at a variable frequency, as represented by block 415. Thevariable frequency may be set to a slower frequency than the monitoredfrequency (e.g., every 15 minutes, or some other slower frequency). Inone embodiment, the variable frequency may be adjusted to the samplingfrequency, which may be the same frequency or faster frequency than themonitored frequency.

The variable frequency is adjusted based on the monitored analytelevels. The analyte levels recorded at the variable frequency (e.g.,stored within memory) may then be sent to remote receiving device (e.g.,an analyte monitoring device, such as an glucose meter or reader) toprovide historical analyte levels for the subject. The logged historicaldata may be stored over a longer period of time to provide sufficienthistorical data for analysis.

In one embodiment, the monitoring of the analyte level data at the firstfrequency includes storing the data in memory—e.g., keeping a rollinglog of data for a predetermined period of time. In this way, the datamay be accessed and analyzed to determine whether to adjust the variablefrequency higher or lower and by how much. In another embodiment, theanalyte level data is processed on the fly in real-time and the variablefrequency adjusted accordingly.

For example, an on body unit including sensor electronics coupled to anin-vivo positioned glucose sensor can monitor the glucose levels at thesampling rate of a sample per minute, and keep a rolling log of 16minutes of glucose levels. Every 15 minutes, a glucose level is loggedand stored in memory. The 16 minute rolling log of glucose data isanalyzed or otherwise processed (e.g., by a processor of the sensorelectronics) to determine whether to adjust the variable frequency andby how much. For instance, if the glucose data in the 16 minute rollinglog is steady or slow changing (e.g., below a predetermined thresholdrate-of-change), then the processor records the variable data at aslower frequency than if the glucose data in the 16 minute rolling logis rapidly changing. The variable data stored in memory may then besubsequently communicated (e.g., wirelessly) to a glucose monitoringdevice, such as a glucose meter or reader.

In some aspects, analyte levels are monitored at a faster frequency thanthe frequency at which the analyte levels are logged or otherwiserecorded in memory, but the frequency of the variable data is adjustedbased upon communications with an analyte monitoring device or otherdevice. The analyte monitoring device or other device may communicatefrequency-adjusting information to the sensor electronics of the on bodyunit that is then used to determine whether to adjust the recordingfrequency of the variable data. The communication of the informationand/or the adjustments of the recording frequency may occur at discretetimes or otherwise be performed dynamically in real-time.

In one embodiment, the variable data frequency may be adjusted based oneor more of the following: information for certain preset conditions(e.g., time of day, user indicated activity, etc.); input informationfrom a device (e.g., a pedometer or accelerometer (e.g., for exercise orsleep); information relating to an insulin pump, smart pen, boluscalculator (e.g., for meal or insulin delivery), etc.), etc.

FIG. 6 illustrates a flowchart for logging or otherwise recording dataat a variable frequency, according to one embodiment. At block 505,analyte levels derived from an in-vivo positioned sensor are received.For example, sensor electronics coupled to an in-vivo positioned analytesensor of an on body unit may receive the analyte levels derived fromthe in-vivo positioned analyte sensor as they are sampled. The analytelevel data is logged into memory at a variable frequency. At block 515,the sensor electronics receive frequency-adjusting information from ananalyte monitoring device or other analyte-related device configured tocommunicate with the sensor electronics. The devices may be in constantcommunication range, or brought into communication range at varioustimes for instance. At block 520, the sensor electronics adjusts thefrequency at which the variable data is recorded based on thefrequency-adjusting information. For instance, the frequency may beincreased around meal times, during exercise, before and after insulinadministration times. The frequency may be decreased, for instance,during sleeping hours or other times when glucose would be expected tobe most stable. The preceding adjustments are exemplary, and thevariable frequency may be adjusted according to any predefinedparameters or criteria.

Randomly Acquiring or Logging Analyte Levels:

In some aspects, methods, devices, and systems related to analytemonitoring with in-vivo positioned analyte sensors by acquiring orstoring analyte levels from the in-vivo positioned analyte sensor atrandomly determined periods of time. In this way, for example, diagnosisor evaluation of subjects (e.g., diabetic patients) may not rely solelyon point-in-time analyte levels (e.g., fasting glucose analyte levels,etc.) or a single number that reflects the average glucose level over a3 month period (e.g., A1c analyte levels, etc.).

In one embodiment, an on body unit is activated to begin a randomtesting process in which analyte levels are randomly sampled orotherwise acquired. The activation of the random testing process by themicroprocessor can be done externally, for example, such as by bringingan analyte monitoring device into communication range with the on bodyunit.

The testing process is random in that there is no preprogrammed scheduleof times to perform a testing, or pre-programmed frequency at whichtestings are performed. The user of the device, whether the doctor,health care provider, or patient, does not select or choose the testingschedule or frequency of the testing times. Instead, the sensorelectronics (e.g., processor) of the on body unit randomly determinesthe testing times at which a testing is performed. The testing may bedetermined under broad constraints not specific to the times at whichthe testings are performed, however, such as a predetermined or minimalnumber of readings, or a predetermined or minimal number of readings ina predetermined time period, etc. For instance, a broad constraint maybe that 6 glucose readings are to be performed in a 24-hour period.These values are exemplary and other numbers of readings or time periodsmay be implemented. The constraints may be based on both clinicalfactors (e.g., minimal number of readings that are required to makeuseful clinical decisions) and technical considerations (e.g., memorycapacity of storage unit within the sensor). However, the actual timingof the performance of the testing is random.

Following activation, the processor determines the time at which theanalyte level (e.g., glucose level) is stored in memory. In oneembodiment, the sensor measures the analyte level only at the time whenthe analyte level is to be stored in memory. For example, using theexample of 6 glucose readings in a 24-hour period, the following is anexample of random times at which a glucose reading is measured andrecorded in memory. The example is not intended to be limiting.

Day 1: 2 am, 7 am, 3 pm, 8 pm, 10 pm, and 11 pm

Day 2: 5 am, 8 am, 10 am, 11 am, 6 pm, 11 pm

Day 3: 1 am, 10 am, 11 am, 3 pm, 5 pm, 9 pm

. . .

Day n: 1 am, 3 am, 5 am, 2 pm, 8 pm, 11 pm

In another embodiment, the on body unit is configured to providemeasurements of analyte levels at a predetermined schedule, however theanalyte level is stored in memory at randomly generated times. Forexample, the sensor may measure glucose at some predetermined schedule(e.g., 7 AM, 8 AM, 9 AM . . . ); however, the glucose reading at allthese times would not be stored. Only glucose data that would be storedwould be that measured at some randomly generated times (e.g., 7 AM, 8AM, 11 AM, 5 PM . . . ).

The on body unit may then, for instance, communicate (e.g., wired orwirelessly) with the analyte monitoring device to send the randomlystored analyte levels to the analyte monitoring device. The analytemonitoring device, such as any variety of hand-held measurementinstruments or analysis instruments, such as a reader for instance. Theanalyte monitoring device may also be another data processing devicesuch as a personal computer, laptop, cell phone or smartphone, personaldigital assistant (PDA), etc.

In one embodiment, the subject has the on body unit coupled to theirbody with the analyte sensor positioned in vivo for a fixed amount oftime. Various values of the fixed amount of time may be implemented invarious embodiments. For example, in some instances, the fixed amount oftime may be a value between two to 30 days, such as five to ten days.Other fixed amounts of time may also be implemented.

FIG. 7 illustrates a flowchart for randomly acquiring analyte levelsfrom an in-vivo positioned analyte sensor for subsequent analysis,according to one embodiment. At block 605, an on body unit is activatedwith the analyte sensor positioned in vivo on a subject. At block 610,analyte levels are acquired at random times during a collectionperiod—e.g., from the in-vivo positioned analyte sensor. The randomlyacquired analyte data is then stored in memory of the on body unit andsubsequently sent to an analyte monitoring device configured tocommunicate with the on body unit—e.g., when the user initiates acommunication between the analyte monitoring device and the on bodyunit, as represented by block 615. The analyte monitoring device maythen send the randomly acquired analyte levels to another dataprocessing device, such as a laptop, computer, smartphone, etc., or to aserver via an internet connection, etc., for access by a physician orhealth care provider for instance, as represented by block 620.

In one embodiment, the randomly acquired analyte levels for the entirecollection period is stored and sent to an analyte monitoring device ordata processing device during a single communication. In anotherembodiment, the randomly acquired analyte levels for the entirecollection period is sent to an analyte monitoring device or dataprocessing device over multiple communications. For instance, thesubject may initiate communications between the on body unit and ananalyte monitoring device by bringing the analyte monitoring device incommunication range of the on body unit), whereby any randomly acquiredanalyte levels stored in memory at the time of the communication is sentto the analyte monitoring device.

The physician or health care provider may then obtain the randomlystored analyte data for the entire collection period. For instance, thephysician may upload the data from the subject's analyte monitoringdevice, or from the on body unit, when the subject returns for a followup visit. Alternatively, the physician may have access to the storedanalyte data after the subject uploads the data from the analytemonitoring device to a hospital server via the internet.

FIG. 8 illustrates a flowchart for a method of providing therapeuticrecommendations based on randomly acquired analyte levels derived froman in-vivo positioned analyte sensor. At block 705, an on body unit ispositioned in vivo on a subject. The on body unit is activated, as showat block 710. Analyte levels are randomly acquired and stored in memoryin the sensor electronics. At block 715, the randomly acquired analytelevels are retrieved by the physician or health care provider (e.g.,from the subject's analyte monitoring device, from the on body unit, orfrom the hospital server after the subject uploads the data via theinternet, etc.). One or more plots are generated from the randomlyacquired analyte levels, as represented by block 720. The plots mayinclude, for example, curves of average analyte readings and/or one ormore standard deviation lines (e.g., +/−65% range, +/−90% range, etc.)over a predetermined time period, such as a 24-hour period, etc. Thephysician or health care provider may then review the plot and provide atherapeutic recommendation based on the generated plot, as representedby block 725.

FIG. 9 illustrates a plot of randomly acquired glucose levels derivedfrom an on body unit, according to one embodiment. Plot 800 includesrandomly acquired glucose levels 805 derived from an in-vivo positionedglucose sensor over six days. An average glucose curve 850 generatedfrom the randomly acquired analyte levels 805 is shown on the plot. Alsoshown are the standard deviation curves 840 generated from the randomlyacquired analyte levels 805.

Configuring Recording Parameters:

Various analyte monitoring devices and systems may require differentdesign parameters, such as memory size needed (e.g., to save sufficientdata, save space, or to save on cost), and/or the appropriate samplingor recording rate or interval, etc.

In some embodiments, the analyte levels are sent to an analytemonitoring device, which remains in communication range with the on bodyunit. In other embodiments, the analyte levels are sent to an analytemonitoring device, which is brought in and out of communication rangewith the on body unit. Further, analyte monitoring devices and systemsmay be used to provide various analyte related data. For example,glucose systems may in some instances provide the user with real-timeglucose information to make an insulin dosing decision; “trends” orrate-of-change information—e.g., an instantaneous value of therate-of-change represented as a change in glucose concentration perdelta time; or “trend” information that represents characteristics ofglucose values with respect to the rate-of-change, such as increasing(e.g., rising), increasing rapidly, decreasing (e.g., falling),decreasing rapidly, remaining level (e.g., stable), etc. Still further,analyte monitoring systems may also store past analyte values andpresent one or more of the past values to the user. In some instance asingle past value (e.g., the most recent past value) may be presented.In other instances, multiple glucose values may be presented over a timeperiod—e.g., over the last hour, 8 hours, 12 hours, 24 hours, etc.

The specific implementation and application of the device or system mayrequire different design parameters (e.g., memory sizes, sampling rates,etc.) for optimum monitoring. For instance, the amount of memory neededfor historic data may depend on various factors, such as how the systemis used, etc. For example, a system intended for viewing historical dataretrospectively may be include sufficient memory to store the historicaldata obtained between transfers of the data to the reader. Furthermore,memory size may be affected by cost and space of a device. Having toomuch memory burdens every unit with the cost of extra memory and furthermay take up more physical space on the circuit board. Having too littlememory may be detrimental to providing enough information to the user tobe useful.

The rate at which data points are stored (e.g., every minute, every fiveminutes, every 10 minutes, etc.) may vary depending on application. Insome embodiments, the all sampled data is stored, such that therecording interval or frequency is equal to the sampling intervalfrequency. In some cases, analyte system may be used by an insulindependent user to make insulin dosing decisions. In such case, thesystem needs sufficient memory to retain history for the longer ofuser's insulin action time (e.g., the time for the insulin taken by theuser to effectively run its course in the body of the user) and/orcarbohydrate action time (e.g., the time for carbohydrates toeffectively run its course in the body of the user). These times may beaffected by any number of factors, such as a user's physiologicalcharacteristics, type of insulin (e.g., short-acting or long-actinginsulin), etc. In some instances, for example, these times may be on theorder of a few hours.

Furthermore, the historical recording time or duration, and the numberof minutes between saved data points (e.g., the recording rate) may varydepending on the specifics of the application, and/or an individualuser's physiological time constant, etc. For instance, the designparameters may be selected by a system designer to save data oftenenough that significant analyte data points are not missed.

In some aspects of the present disclosure, methods, devices, and systemsare provided that enable the configuration of the recording parametersas the system is being used or otherwise operated. The recordingparameters may include, for example, the recording duration (e.g., theduration of time that data points should be sampled and stored), therecording rate (e.g., the intervals between samples), etc.

For example, a system designer and/or a user (e.g., a physician, healthcare provider, patient, etc.) may configure the recording parameters asthe system is being used or otherwise operated. In this way, forexample, the on body unit may be designed with a modest amount of memoryand the system designer and/or user may make the best use of theavailable memory already implemented in the device. This may provide thebenefit, for example, of postponing the decision of how to allocate logmemory to fit diverse needs at least until manufacturing time. In thisway, the software development process is benefited as the time intervalcan be changed without a code change and quality assurance cycle. Forexample, if two or more distinct uses for the on body unit (e.g., maskedor unmasked use), then the settings may be adjusted as the system isactivated by the user, saving the cost of documenting and stockingdifferent parts for instance.

In one embodiment, for example, the system designer or user may initiateone or more commands to provide the on body unit with user configurationdata. For example, the historical data period may be passed from theanalyte monitoring device to the on body unit in the commands. Thesystem may then calculate a sampling rate using the user configurationdata as well as specification data for the on body unit (e.g., theavailable memory for storing analyte values). For example, if the onbody unit has memory for 24 data points, and user configuration dataindicates that a user's insulin action time is 4 hours, the on body unitmay be configured to save a historical data point every 10 minutes(e.g., 4 hours*60 minutes per hour/24 samples=10 minutes per sample). Asanother example, a user reads a glucose value at least once every 12hours and does not want to miss any data for retrospective analysis. Insuch case, for example, if the memory capacity is 24 data points, thenthe on body unit may be configured to save historical data every 30minutes (e.g., 12 hours*60 minutes per hour/24 samples=30 minutes persample.

FIG. 10 illustrates a flowchart for configuring sensor electronics ofthe on body unit to operate at a calculated sampling rate, according tocertain embodiments. After the sensor electronics execute acommunication with the analyte monitoring device (e.g., analyte reader)at block 905, the sensor electronics receives the user configurationdata from the analyte monitoring device, as represented by block 908.The sensor electronics calculate the sampling rate with the userconfiguration data and specification data that is stored in memory ofthe sensor electronics for instance, as shown by block 910, and then thesensor electronics are configured to sample the in-vivo positionedanalyte sensor at the calculated sampling rate, as shown by block 915.The sensor electronics obtains analyte levels at the sampling rate, asshown at block 918, and eventually sends the analyte measurements to ananalyte monitoring device or other data processing device, as shown atblock 920.

Devices and Systems

In some aspects, the present disclosure relates to the detecting of atleast one analyte, including glucose, in body fluid. For example,embodiments may relate to in vivo monitoring of the level of one or moreanalytes using analyte monitoring device or system and/or thecommunication of the data derived therefrom. For instance, the systemmay include an analyte sensor at least a portion of which is to bepositioned beneath a skin surface of a user for a period of time.

Embodiments may include combined or combinable devices, systems andmethods and/or transferring data within or between an on body unit andan analyte monitoring device. In one embodiment, the systems, or atleast a portion of the systems, are integrated into a single unit. Insome aspects, the devices, systems, and methods may relate to dataprocessing devices (e.g., a computer, laptop, mobile phone, personalcomputer, or any other data processing device) that receive or otherwiseobtain data derived from the described analyte monitoring systems anddevices.

The analyte monitoring devices and systems may include, or communicatewith, an on body unit including an analyte sensor at least a portion ofwhich is positionable beneath the skin surface of the user for the invivo detection of an analyte, including glucose, lactate, and the like,in a body fluid. Embodiments include wholly implantable analyte sensorsand analyte sensors in which only a portion of the sensor is positionedunder the skin and a portion of the sensor resides above the skin, e.g.,for contact to a sensor control unit (which may include a communicationmodule or the like), a receiver/display unit, transceiver, processor,etc. The sensor may be, for example, positionable in vivo in a user forthe monitoring of a level of an analyte in the user's interstitialfluid.

An analyte sensor may be positioned in contact with interstitial fluidto detect the level of glucose, which detected glucose may be used toinfer the glucose level in the user's bloodstream. Embodiments of theanalyte sensors may be configured for monitoring the level of theanalyte over a time period which may range from seconds, minutes, hours,days, weeks, to months, or longer. In some instances, the analytesensors, such as glucose sensors, are capable of in vivo detection of ananalyte for one hour or more, e.g., a few hours or more, e.g., a fewdays or more, e.g., three or more days, e.g., five days or more, e.g.,seven days or more, e.g., several weeks or more, or one month or more.

Embodiments of the present disclosure may relate to the transferring orcommunication (e.g., logging, storing, communicating, etc.) of the dataderived from an analyte monitoring device or system.

As demonstrated herein, the methods of the present disclosure are usefulin connection with a device or system that is used to measure or monitoran analyte (e.g., glucose), and/or communicate or process data derivedfrom the measurement or monitoring of an analyte, such as any suchdevice described herein. These methods may also be used in connectionwith a device that is used to measure or monitor another analyte (e.g.,ketones, ketone bodies, HbA1c, and the like), including oxygen, carbondioxide, proteins, drugs, or another moiety of interest, for example, orany combination thereof, found in bodily fluid, including subcutaneousfluid, dermal fluid (sweat, tears, and the like), interstitial fluid, orother bodily fluid of interest, for example, or any combination thereof.

FIG. 11 shows an analyte (e.g., glucose) monitoring system, according toone embodiment. Aspects of the subject disclosure are further describedprimarily with respect to glucose monitoring devices and systems, andmethods of glucose detection, for convenience only and such descriptionis in no way intended to limit the scope of the embodiments. It is to beunderstood that the analyte monitoring system may be configured tomonitor a variety of analytes at the same time or at different times.

Analytes that may be monitored include, but are not limited to, acetylcholine, amylase, bilirubin, cholesterol, chorionic gonadotropin,glycosylated hemoglobin (HbA1c), creatine kinase (e.g., CK-MB),creatine, creatinine, DNA, fructosamine, glucose, glucose derivatives,glutamine, growth hormones, hormones, ketones, ketone bodies, lactate,peroxide, prostate-specific antigen, prothrombin, RNA, thyroidstimulating hormone, and troponin. The concentration of drugs, such as,for example, antibiotics (e.g., gentamicin, vancomycin, and the like),digitoxin, digoxin, drugs of abuse, theophylline, and warfarin, may alsobe monitored. In embodiments that monitor more than one analyte, theanalytes may be monitored at the same or different times.

The analyte monitoring system 1400 includes an analyte sensor 1401, adata processing unit 1402 connectable to the sensor 1401, and a primaryreceiver unit 1404. In some instances, the primary receiver unit 1404 isconfigured to communicate with the data processing unit 1402 via acommunication link 1403. In one embodiment, the primary receiver unit1404 may be further configured to communicate data to a data processingterminal 1405 to evaluate or otherwise process or format data receivedby the primary receiver unit 1404. The data processing terminal 1405 maybe configured to receive data directly from the data processing unit1402 via a communication link 1407, which may optionally be configuredfor bi-directional communication. Further, the data processing unit 1402may include a communication unit or a transceiver to communicate and/orreceive data to and/or from the primary receiver unit 1404 and/or thedata processing terminal 1405 and/or optionally a secondary receiverunit 1406.

Also shown in FIG. 11 is an optional secondary receiver unit 1406 whichis operatively coupled to the communication link 1403 and configured toreceive data communicated from the data processing unit 1402. Thesecondary receiver unit 1406 may be configured to communicate with theprimary receiver unit 1404, as well as the data processing terminal1405. In one embodiment, the secondary receiver unit 1406 may beconfigured for bi-directional wireless communication with each of theprimary receiver unit 1404 and the data processing terminal 1405. Asdiscussed in further detail below, in some instances, the secondaryreceiver unit 1406 may be a de-featured receiver as compared to theprimary receiver unit 1404, for instance, the secondary receiver unit1406 may include a limited or minimal number of functions and featuresas compared with the primary receiver unit 1404. As such, the secondaryreceiver unit 1406 may include a smaller (in one or more, including all,dimensions), compact housing or embodied in a device including a wristwatch, arm band, PDA, mp3 player, cell phone, etc., for example.Alternatively, the secondary receiver unit 106 may be configured withthe same or substantially similar functions and features as the primaryreceiver unit 1404. The secondary receiver unit 106 may include adocking portion configured to mate with a docking cradle unit forplacement by, e.g., the bedside for night time monitoring, and/or abi-directional communication device. A docking cradle may recharge apower supply.

Only one analyte sensor 1401, data processing unit 1402 and dataprocessing terminal 1405 are shown in the embodiment of the analytemonitoring system 1400 illustrated in FIG. 11. However, the analytemonitoring system 1400 may include more than one sensor 1401 and/or morethan one data processing unit 1402, and/or more than one data processingterminal 1405. Multiple sensors may be positioned in a user for analytemonitoring at the same or different times.

The analyte monitoring system 1400 may be a continuous monitoringsystem, or semi-continuous, or a monitoring system that provides fortransfer of analyte levels only upon brining of the on body unit andanalyte monitoring device in signal communication with one another(flash). In a multi-component environment, each component may beconfigured to be uniquely identified by one or more of the othercomponents in the system so that communication conflict may be readilyresolved between the various components within the analyte monitoringsystem 1400. For example, unique IDs, communication channels, and thelike, may be used.

In one embodiment, the sensor 1401 is physically positioned in or on thebody of a user whose analyte level is being monitored. The sensor 1401may be configured to at least periodically sample the analyte level ofthe user and convert the sampled analyte level into a correspondingsignal for communication by the data processing unit 1402. The dataprocessing unit 1402 is coupleable to the sensor 1401 so that bothdevices are positioned in or on the user's body, with at least a portionof the analyte sensor 1401 positioned transcutaneously. The dataprocessing unit may include a fixation element, such as an adhesive orthe like, to secure it to the user's body. A mount (not shown)attachable to the user and mateable with the data processing unit 1402may be used. For example, a mount may include an adhesive surface. Thedata processing unit 1402 performs data processing functions, where suchfunctions may include, but are not limited to, filtering and encoding ofdata signals, each of which corresponds to a sampled analyte level ofthe user, for communication to the primary receiver unit 1404 via thecommunication link 1403. In one embodiment, the sensor 1401 or the dataprocessing unit 1402 or a combined sensor/data processing unit may bewholly implantable under the skin surface of the user.

In one embodiment, the primary receiver unit 1404 may include an analoginterface section including an RF receiver and an antenna that isconfigured to communicate with the data processing unit 1402 via thecommunication link 1403, and a data processing section for processingthe received data from the data processing unit 1402 including datadecoding, error detection and correction, data clock generation, databit recovery, etc., or any combination thereof.

In operation, the primary receiver unit 1404 in one embodiment isconfigured to synchronize with the data processing unit 1402 to uniquelyidentify the data processing unit 1402, based on, for example, anidentification information of the data processing unit 1402, andthereafter, to periodically receive signals communicated from the dataprocessing unit 1402 associated with the monitored analyte levelsdetected by the sensor 1401.

Referring again to FIG. 11, the data processing terminal 1405 mayinclude a personal computer, a portable computer including a laptop or ahandheld device such as a consumer electronics device (e.g., a personaldigital assistant (PDA), a telephone including a cellular phone (e.g., amultimedia and Internet-enabled mobile phone including an iPhone™, aBlackberry®, or similar phone), an mp3 player (e.g., an iPOD™, etc.), apager, and the like), and/or a drug delivery device (e.g., an infusiondevice), each of which may be configured for data communication with thereceiver via a wired or a wireless connection. Additionally, the dataprocessing terminal 1405 may further be connected to a data network (notshown) for storing, retrieving, updating, and/or analyzing datacorresponding to the detected analyte level of the user.

The data processing terminal 1405 may include a drug delivery device(e.g., an infusion device) such as an insulin infusion pump or the like,which may be configured to administer a drug (e.g., insulin) to theuser, and which may be configured to communicate with the primaryreceiver unit 104 for receiving, among others, the measured analytelevel. Alternatively, the primary receiver unit 1404 may be configuredto integrate an infusion device therein so that the primary receiverunit 1404 is configured to administer an appropriate drug (e.g.,insulin) to users, for example, for administering and modifying basalprofiles, as well as for determining appropriate boluses foradministration based on, among others, the detected analyte levelsreceived from the data processing unit 1402. An infusion device may bean external device or an internal device, such as a device whollyimplantable in a user.

In one embodiment, the data processing terminal 1405, which may includean infusion device, e.g., an insulin pump, may be configured to receivethe analyte signals from the data processing unit 1402, and thus,incorporate the functions of the primary receiver unit 1404 includingdata processing for managing the user's insulin therapy and analytemonitoring. In one embodiment, the communication link 1403, as well asone or more of the other communication interfaces shown in FIG. 11, mayuse one or more wireless communication protocols, such as, but notlimited to: an RF communication protocol, an infrared communicationprotocol, a Bluetooth enabled communication protocol, an 802.11xwireless communication protocol, or an equivalent wireless communicationprotocol which would allow secure, wireless communication of severalunits (for example, per Health Insurance Portability and AccountabilityAct (HIPPA) requirements), while avoiding potential data collision andinterference.

FIG. 12 is a block diagram of the data processing unit 1402 shown inFIG. 11 in accordance with one embodiment. Data processing unit 1402includes an analog interface 1501 configured to communicate with thesensor 1401 (FIG. 1), a user input 1502, and a temperature measurementsection 1503, each of which is operatively coupled to processor 1504such as a central processing unit (CPU). Furthermore, unit 1402 is shownto include a serial communication section 1505, clock 1508, and acommunication unit 1506, each of which is also operatively coupled tothe processor 1504. Moreover, a power supply 1507 such as a battery isalso provided in unit 1402 to provide the necessary power.

In another embodiment, the data processing unit may not include allcomponents in the exemplary embodiment shown. User input and/orinterface components may be included or a data processing unit may befree of user input and/or interface components. In one embodiment, oneor more application-specific integrated circuits (ASIC) may be used toimplement one or more functions or routines associated with theoperations of the data processing unit (and/or receiver unit) using forexample one or more state machines and buffers.

As can be seen in the embodiment of FIG. 12, the analyte sensor 1401(FIG. 1) includes four contacts, three of which are electrodes: a workelectrode (W) 1510, a reference electrode (R) 1512, and a counterelectrode (C) 1513, each operatively coupled to the analog interface1501 of the data processing unit 1402. This embodiment also shows anoptional guard contact (G) 1511. Fewer or greater electrodes may beemployed. For example, the counter and reference electrode functions maybe served by a single counter/reference electrode. In some cases, theremay be more than one working electrode and/or reference electrode and/orcounter electrode, etc.

FIG. 13 is a block diagram of an embodiment of a receiver/monitor unitsuch as the primary receiver unit 1404 of the analyte monitoring systemshown in FIG. 11. The primary receiver unit 1404 includes one or moreof: a test strip interface 1601, an RF receiver 1602, a user input 1603,an optional temperature detection section 1604, and a clock 1605, eachof which is operatively coupled to a processing and storage section1607. The primary receiver unit 1404 also includes a power supply 1606operatively coupled to a power conversion and monitoring section 1608.Further, the power conversion and monitoring section 1608 is alsocoupled to the processing and storage section 1607. Moreover, also shownare a receiver serial communication section 1609, and an output 1610,each operatively coupled to the processing and storage section 1607. Theprimary receiver unit 1404 may include user input and/or interfacecomponents or may be free of user input and/or interface components.

In one embodiment, the test strip interface 1601 includes an analytetesting portion (e.g., a glucose level testing portion) to receive ablood (or other body fluid sample) analyte test or information relatedthereto. For example, the test strip interface 1601 may include a teststrip port to receive a test strip (e.g., a glucose test strip). Thedevice may determine the analyte level of the test strip, and optionallydisplay (or otherwise notice) the analyte level on the output 1610 ofthe primary receiver unit 1404. Any suitable test strip may be employed,e.g., test strips that only require a very small amount (e.g., 3microliters or less, e.g., 1 microliter or less, e.g., 0.5 microlitersor less, e.g., 0.1 microliters or less), of applied sample to the stripin order to obtain accurate glucose information. Embodiments of teststrips include, e.g., Freestyle® and Precision® blood glucose teststrips from Abbott Diabetes Care, Inc. (Alameda, Calif.). Glucoseinformation obtained by an in vitro glucose testing device may be usedfor a variety of purposes, computations, etc. For example, theinformation may be used to calibrate sensor 1401, confirm results ofsensor 1401 to increase the confidence thereof (e.g., in instances inwhich information obtained by sensor 1401 is employed in therapy relateddecisions), etc.

In further embodiments, the data processing unit 1402 and/or the primaryreceiver unit 1404 and/or the secondary receiver unit 1406, and/or thedata processing terminal/infusion device 1405 may be configured toreceive the analyte value wirelessly over a communication link from, forexample, a blood glucose meter. In further embodiments, a usermanipulating or using the analyte monitoring system 1400 (FIG. 11) maymanually input the analyte value using, for example, a user interface(for example, a keyboard, keypad, voice commands, and the like)incorporated in one or more of the data processing unit 1402, theprimary receiver unit 1404, secondary receiver unit 1406, or the dataprocessing terminal/infusion device 1405.

The features and techniques described in the present disclosure may beperformed, for example, by the processing circuitry within the dataprocessing unit 1402 or receiving unit 1404, or combination of both. Forexample, in certain embodiments, one or more of the above-describedmethods may be performed entirely within the sensor electronics coupledto the in vivo positioned analyte sensor. In yet other embodiments, oneor more of the above-described methods may be performed entirely withinthe receiver unit or electronics that receive the analyte levels fromthe sensor electronics. In yet other embodiments, one or more of theabove-described methods may be performed by a combination of the sensorelectronics and receiver electronics. In yet other embodiments, one ormore of the above-describe methods may be performed entirely, or inpart, by a data processing device that is provided with the analytelevels derived from the in vivo positioned analyte sensor.

Additional detailed descriptions are provided in U.S. Pat. Nos.5,262,035; 5,264,104; 5,262,305; 5,320,715; 5,593,852; 6,175,752;6,650,471; 6,746, 582, and 7,811,231, each of which is incorporatedherein by reference in their entirety.

In one embodiment of the present disclosure, the analyte monitoringdevice includes processing circuitry that is able to determine a levelof the analyte and activate an alarm system if the analyte level exceedsa threshold. The analyte monitoring device, in these embodiments, has analarm system and may also include a display, such as an LCD or LEDdisplay.

A threshold value is exceeded if the datapoint has a value that isbeyond the threshold value in a direction indicating a particularcondition. For example, a datapoint which correlates to a glucose levelof 200 mg/dL exceeds a threshold value for hyperglycemia of 180 mg/dL,because the datapoint indicates that the user has entered ahyperglycemic state. As another example, a datapoint which correlates toa glucose level of 65 mg/dL exceeds a threshold value for hypoglycemiaof 70 mg/dL because the datapoint indicates that the user ishypoglycemic as defined by the threshold value. However, a datapointwhich correlates to a glucose level of 75 mg/dL would not exceed thesame threshold value for hypoglycemia because the datapoint does notindicate that particular condition as defined by the chosen thresholdvalue.

An alarm may also be activated if the sensor readings indicate a valuethat is beyond a measurement range of the sensor. For glucose, thephysiologically relevant measurement range may be 30-400 mg/dL,including 40-300 mg/dL and 50-250 mg/dL, of glucose in the interstitialfluid.

The alarm system may also, or alternatively, be activated when the rateof change or acceleration of the rate of change in analyte levelincrease or decrease reaches or exceeds a threshold rate oracceleration. For example, in the case of a subcutaneous glucosemonitor, the alarm system might be activated if the rate of change inglucose concentration exceeds a threshold value which might indicatethat a hyperglycemic or hypoglycemic condition is likely to occur.

A system may also include system alarms that notify a user of systeminformation such as battery condition, calibration, sensor dislodgment,sensor malfunction, etc. Alarms may be, for example, auditory and/orvisual. Other sensory-stimulating alarm systems may be used includingalarm systems which heat, cool, vibrate, or produce a mild electricalshock when activated.

Drug Delivery System

The present disclosure also includes sensors used in sensor-based drugdelivery systems. The system may provide a drug to counteract the highor low level of the analyte in response to the signals from one or moresensors. Alternatively, the system may monitor the drug concentration toensure that the drug remains within a desired therapeutic range. Thedrug delivery system may include one or more (e.g., two or more)sensors, a processing unit, a receiver/display unit, and a drugadministration system. In some cases, some or all components may beintegrated in a single unit. A sensor-based drug delivery system may usedata from the one or more sensors to provide necessary input for acontrol algorithm/mechanism to adjust the administration of drugs, e.g.,automatically or semi-automatically. As an example, a glucose sensor maybe used to control and adjust the administration of insulin from anexternal or implanted insulin pump.

Each of the various references, presentations, publications, provisionaland/or non-provisional U.S. patent applications, U.S. patents, non-U.S.patent applications, and/or non-U.S. patents that have been identifiedherein, is incorporated herein by reference in its entirety.

Other embodiments and modifications within the scope of the presentdisclosure will be apparent to those skilled in the relevant art.Various modifications, processes, as well as numerous structures towhich the embodiments of the present disclosure may be applicable willbe readily apparent to those of skill in the art to which the presentdisclosure is directed upon review of the specification. Various aspectsand features of the present disclosure may have been explained ordescribed in relation to understandings, beliefs, theories, underlyingassumptions, and/or working or prophetic examples, although it will beunderstood that the present disclosure is not bound to any particularunderstanding, belief, theory, underlying assumption, and/or working orprophetic example. Although various aspects and features of the presentdisclosure may have been described largely with respect to applications,or more specifically, medical applications, involving diabetic humans,it will be understood that such aspects and features also relate to anyof a variety of applications involving non-diabetic humans and any andall other animals. Further, although various aspects and features of thepresent disclosure may have been described largely with respect toapplications involving partially in vivo positioned sensors, such astranscutaneous or subcutaneous sensors, it will be understood that suchaspects and features also relate to any of a variety of sensors that aresuitable for use in connection with the body of an animal or a human,such as those suitable for use as fully implanted in the body of ananimal or a human. Finally, although the various aspects and features ofthe present disclosure have been described with respect to variousembodiments and specific examples herein, all of which may be made orcarried out conventionally, it will be understood that the invention isentitled to protection within the full scope of the appended claims.

Additional Example Embodiments

In some aspects, methods of recording sampled analyte levels with an onbody unit are provided that include obtaining analyte levels derivedfrom an in vivo sensor sampled at sampling intervals; and recording,with a processor, sampled analyte levels in memory at recordingintervals. The recording intervals include more than one samplinginterval. The recorded analyte levels are subject to a validitydetermination before being recorded. One or more of the validitydeterminations are performed on a sampled analyte level coinciding witha time point of a recording interval, and one or more of the validitydeterminations are performed on a sampled analyte level not coincidingwith a time point of a recording interval.

In certain embodiments, the methods include selecting a first sampledanalyte level coinciding with a first time point of the recordingintervals; performing a first validity determination on the firstcoinciding analyte level; determining the first coinciding analyte levelis valid; and recording the first coinciding analyte level determined isvalid.

In certain embodiments, the methods include selecting a second sampledanalyte level coinciding with a second time point of the recordingintervals; performing a second validity determination on the secondcoinciding analyte level; determining the second coinciding analytelevel is invalid; selecting a first alternative analyte level forvalidity determination; and performing a third validity determination onthe first alternative analyte level. Further, the first alternativeanalyte level is a sampled analyte level that does not coincide with atime point of the recording intervals.

In certain embodiments, the methods include determining the firstalternative analyte level is valid; and recording the first alternativeanalyte level instead of the second coinciding analyte level.

In certain embodiments, the methods include determining the firstalternative analyte level is invalid; and selecting a second alternativeanalyte level for validity determination; performing a fourth validitydetermination on the second alternative analyte level; determining thesecond alternative analyte level is valid; and recording the secondalternative analyte level instead of the second coinciding analytelevel. Further, the second alternative analyte level is a sampledanalyte level that does not coincide with a time point of the recordingintervals.

In certain embodiments, the methods include determining the firstalternative analyte level is invalid; and selecting one or morealternative analyte levels for validity determinations; performing avalidity determination on each of the one or more alternative analytelevels until a valid determination is made; and recording an alternativeanalyte level generating the valid determination instead of the secondcoinciding analyte level. Further, the one or more alternative analytelevels are sampled analyte levels that do not coincide with a time pointof the recording intervals.

In certain embodiments, the first alternative analyte level is a sampledanalyte level immediately adjacent to the second coinciding analytelevel.

In certain embodiments, each alternative analyte level is distancedwithin a recording window for the second time point, wherein therecording window is defined by recording time points immediately priorto and immediately subsequent to the second time point.

In certain embodiments, an adjusted timestamp is recorded with therecorded alternative analyte level.

In certain embodiments, the methods include selecting a first sampledanalyte level coinciding with a first time point of the recordingintervals; selecting one or more alternative analyte level for validitydetermination; generating a validity metric for the first coincidinganalyte level and the one or more alternative analyte levels; andrecording an analyte level based on the validity metrics for the firstcoinciding analyte level and the one or more alternative analyte levels.Further, the one or more alternative analyte levels are sampled analytelevels that do not coincide with a time point of the recordingintervals. Still further, the validity metrics for the coincidinganalyte level and the one or more alternative analyte levels represent alevel of validity.

In certain embodiments, the validity metrics are weighed based on a timedeviation from the first time point, and wherein the recording of theanalyte level is based on the weighted validity metrics.

In certain embodiments, each of the one or more alternative analytelevels are distanced within a recording window for the first time point,wherein the recording window is defined by recording time pointsimmediately prior to and immediately subsequent to the first time point.

In certain embodiments, missing analyte levels are determined to beinvalid.

In certain embodiments, sampled analyte levels are stored in a buffer.

In certain embodiments, the analyte is glucose or a ketone body.

In some aspects, analyte monitoring devices are provided that include anin-vivo positionable analyte sensor; and sensor electronics coupled tothe in-vivo positionable sensor. The sensor electronics includes aprocessor and memory operably coupled to the processor. The memoryincludes instructions stored therein that, when executed by a processor,cause the processor to obtain analyte levels derived from an in vivosensor sampled at sampling intervals; and record, with a processor,sampled analyte levels in memory at recording intervals, the recordingintervals including more than one sampling interval. The recordedanalyte levels are subject to a validity determination before beingrecorded. The one or more of the validity determinations are performedon a sampled analyte level coinciding with a time point of a recordinginterval. One or more of the validity determinations are performed on asampled analyte level not coinciding with a time point of a recordinginterval.

In certain embodiments, the memory includes instructions stored thereinthat, when executed by a processor, cause the processor to select afirst sampled analyte level coinciding with a first time point of therecording intervals; perform a first validity determination on the firstcoinciding analyte level; determine the first coinciding analyte levelis valid; and record the first coinciding analyte level determined isvalid.

In certain embodiments, the memory includes instructions stored thereinthat, when executed by a processor, cause the processor to select asecond sampled analyte level coinciding with a second time point of therecording intervals; perform a second validity determination on thesecond coinciding analyte level; determine the second coinciding analytelevel is invalid; select a first alternative analyte level for validitydetermination, wherein the first alternative analyte level is a sampledanalyte level that does not coincide with a time point of the recordingintervals; and perform a third validity determination on the firstalternative analyte level.

In certain embodiments, the memory includes instructions stored thereinthat, when executed by a processor, cause the processor to determine thefirst alternative analyte level is valid; and record the firstalternative analyte level instead of the second coinciding analytelevel.

In certain embodiments, the memory includes instructions stored thereinthat, when executed by a processor, cause the processor to determine thefirst alternative analyte level is invalid; and select a secondalternative analyte level for validity determination; performing afourth validity determination on the second alternative analyte level;determining the second alternative analyte level is valid; and recordingthe second alternative analyte level instead of the second coincidinganalyte level. The second alternative analyte level is a sampled analytelevel that does not coincide with a time point of the recordingintervals.

In certain embodiments, the memory includes instructions stored thereinthat, when executed by a processor, cause the processor to determine thefirst alternative analyte level is invalid; select one or morealternative analyte levels for validity determinations; perform avalidity determination on each of the one or more alternative analytelevels until a valid determination is made; and record an alternativeanalyte level generating the valid determination instead of the secondcoinciding analyte level. Further, the one or more alternative analytelevels are sampled analyte levels that do not coincide with a time pointof the recording intervals.

In certain embodiments, the first alternative analyte level is a sampledanalyte level immediately adjacent to the second coinciding analytelevel.

In certain embodiments, each alternative analyte level is distancedwithin a recording window for the second time point, wherein therecording window is defined by recording time points immediately priorto and immediately subsequent to the second time point.

In certain embodiments, an adjusted timestamp is recorded with therecorded alternative analyte level.

In certain embodiments, the memory includes instructions stored thereinthat, when executed by a processor, cause the processor to select afirst sampled analyte level coinciding with a first time point of therecording intervals; select one or more alternative analyte level forvalidity determination; generate a validity metric for the firstcoinciding analyte level and the one or more alternative analyte levels;record an analyte level based on the validity metrics for the firstcoinciding analyte level and the one or more alternative analyte levels.Further, the one or more alternative analyte level s are sampled analytelevels that do not coincide with a time point of the recordingintervals. Further, the validity metrics for the coinciding analytelevel and the one or more alternative analyte levels represent a levelof validity.

In certain embodiments, the validity metrics are weighed based on a timedeviation from the first time point, and wherein the recording of theanalyte level is based on the weighted validity metrics.

In certain embodiments, each of the one or more alternative analytelevels are distanced within a recording window for the first time point,wherein the recording window is defined by recording time pointsimmediately prior to and immediately subsequent to the first time point.

In certain embodiments, missing analyte levels are determined to beinvalid.

In certain embodiments, sampled analyte levels are stored in a buffer.

In certain embodiments, the analyte is glucose or a ketone body.

In some aspects, methods of configuring a recording rate are providedthat include executing a communication between sensor electronics and ananalyte monitoring device; receiving user configuration data at thesensor electronics from the analyte monitoring device; calculating arecording rate for the sensor electronics and in-vivo positioned analytesensor; and configuring the sensor electronics to operate at thecalculated recording rate. The sensor electronics are coupled to anin-vivo positionable sensor and configured to communicate analyte levelsto the analyte monitoring device. The recording rate is calculated basedon user configuration data for the analyte monitoring device; andspecification data for the sensor electronics.

In certain embodiments, the methods include obtaining and storinganalyte levels form the in-vivo positioned analyte sensor at therecording rate; and sending the analyte levels to the analyte monitoringdevice.

In certain embodiments, the user configuration data comprises arecording duration.

In certain embodiments, the recording duration is based on an insulinaction time and/or a carbohydrate action time.

In certain embodiments, the recording duration is based on a user'sreading pattern.

In certain embodiments, the specification data includes sample storagecapacity.

In some aspects, analyte monitoring devices are provided that include anin-vivo positionable analyte sensor; and sensor electronics coupled tothe in-vivo positionable sensor. The sensor electronics include aprocessor; and memory operably coupled to the processor. The memoryincludes instructions stored therein that, when executed by a processor,cause the processor to execute a communication between sensorelectronics and an analyte monitoring device; receive user configurationdata at the sensor electronics from the analyte monitoring device;calculate a recording rate for the sensor electronics and in-vivopositioned analyte sensor; and configuring the sensor electronics tooperate at the calculated recording rate. The sensor electronics arecoupled to an in-vivo positionable sensor and configured to communicateanalyte levels to the analyte monitoring device. The recording rate iscalculated based on: user configuration data for the analyte monitoringdevice; and specification data for the sensor electronics.

In certain embodiments, the memory includes instructions stored thereinthat, when executed by a processor, cause the processor to obtaining andrecording analyte levels form the in-vivo positioned analyte sensor atthe recording rate; and sending the analyte levels to the analytemonitoring device.

In certain embodiments, the user configuration data comprises arecording duration.

In certain embodiments, the recording duration is based on an insulinaction time and/or a carbohydrate action time.

In certain embodiments, the recording duration is based on a user'sreading pattern.

In certain embodiments, the specification data includes sample storagecapacity.

In some aspects, analyte monitoring devices are provided that include acommunication interface for receiving analyte levels derived from an onbody unit including an in-vivo positioned analyte sensor; a display fordisplaying analyte value; a processor; and memory operably coupled tothe processor. The memory includes instructions stored therein that,when executed by a processor, cause the processor to receive firstsensor-use information via the communication interface, wherein thefirst sensor-use information indicates a first type of sensor-use for afirst on body unit; identify first settings associated with the firstsensor-use information, wherein the first settings comprise a setting tooperate in a mode where analyte values are not displayed on the display;configure the analyte monitoring device to operate with the firstsettings; and operate the analyte monitoring device with the firstsettings. Analyte values are not displayed when analyte values arereceived via the communication interface.

In certain embodiments, the first type of sensor-use is for clinicaluse, and wherein the second type of sensor-use is for personal use.

In certain embodiments, the first sensor-use information is receivedduring a communication for initially pairing the analyte monitoringdevice and the sensing device.

In certain embodiments, the sensor-sensor-use information is receivedduring a communication for transferring analyte values from the on bodyunit to the analyte monitoring device.

In certain embodiments, the memory includes instructions stored thereinthat, when executed by a processor, cause the processor to receivesecond sensor-use information via the communication interface, whereinthe second sensor-use information indicates a second type of sensor-usefor a second on body unit; identify second settings associated with thesecond sensor-use information, wherein the second settings comprisesetting to operate in a mode where analyte values are displayed on thedisplay; configure the analyte monitoring device to operate with thesecond settings; and operate the analyte monitoring device with thesecond settings, wherein analyte values are displayed when analytevalues are received via the communication interface.

In some aspects, methods for providing therapeutic recommendations basedon randomly acquired analyte levels derived from the in-vivo positionedsensor are provided. The methods include positioning an analyte sensorin vivo on a subject, the in vivo positioned analyte sensor coupled tosensor electronics, the sensor electronics include a processor andmemory; activating the sensor electronics for operation with the in-vivopositioned analyte sensor; randomly acquiring analyte levels derivedfrom the in-vivo positioned sensor over a predetermined period of timefor collecting data, wherein the analyte levels are stored in the memoryof the sensor electronics; generating a plot from the stored analytelevels; and reviewing the plot to provide therapeutic recommendations.

In certain embodiments, the subject transfers data from the sensorelectronics to an analyte monitoring device, and wherein the analytelevels are retrieved from the analyte monitoring device to generate theplot.

In some aspects, analyte monitoring devices are provided that include anin-vivo positionable sensor; sensor electronics coupled to the in-vivopositionable sensor. The sensor electronics include a processor andmemory, wherein the memory includes instructions stored therein, whichwhen executed by the processor, cause the processor to randomly acquireanalyte levels derived from the in-vivo positionable sensor whenpositioned in-vivo; and send the randomly acquired analyte levels to aremote device.

In certain embodiments, the remote device is an analyte monitoringdevice configured to communicate with the sensor electronics.

In certain embodiments, the randomly acquired analyte levels are sampledat a non-random frequency but stored in memory at randomly generatedtimes.

In some aspects, analyte monitoring systems are provided that include anon body unit, comprising: an in-vivo positionable sensor; sensorelectronics coupled to the in-vivo positionable sensor; and an analytemonitoring device configured to communicate with the on body unit andreceive the randomly acquired analyte levels. The sensor electronicsinclude a processor and memory. The memory includes instructions storedtherein, which when executed by the processor, cause the processor torandomly acquire analyte levels derived from the in-vivo positionablesensor when positioned in-vivo; and send the randomly acquired analytelevels to a remote device.

In certain embodiments, the randomly acquired analyte levels are sampledat a non-random frequency but stored in memory at randomly generatedtimes.

In some aspects, methods for storing analyte levels at a variablefrequency are provided that include receiving sampled analyte levelsderived from an in-vivo positioned sensor; monitoring the sampledanalyte levels at a first frequency; and storing the sampled analytelevels at a second frequency, the second frequency slower than the firstfrequency. The second frequency is variable and determined based on themonitored analyte levels at the first frequency.

In certain embodiments, the second frequency is determined based on arate of change of the monitored analyte levels at the first frequency,wherein the second frequency is larger for larger rates of changes ofthe monitored analyte levels at the first frequency.

In certain embodiments, the second frequency is a first value when therate of change of the monitored analyte levels at the first frequencyexceeds a predetermined threshold, wherein the second frequency is asecond value when the rate of change of the monitored analyte levels atthe first frequency does not exceed the predetermined threshold, whereinthe first value is a higher frequency value than the second value.

In certain embodiments, the first frequency is equal to the samplingfrequency of the analyte levels derived from the in-vivo positionedanalyte sensor.

In certain embodiments, the methods include communicating the storedanalyte levels at the second frequency to an analyte monitoring device.

In certain embodiments, the analyte levels monitored at the firstfrequency is stored for a first period of time, and the stored analytedata logged at the second frequency is logged for a second period oftime, wherein the second period of time is longer in duration than thefirst period of time.

In certain embodiments, the first period of time is less than 1 hour,and the second period of time is greater than 1 hour.

In certain embodiments, the first frequency is less than every 10minutes, and the second frequency is adjustable to greater than every 10minutes.

It should be understood that techniques introduced above can beimplemented by programmable circuitry programmed or configured bysoftware and/or firmware, or they can be implemented entirely byspecial-purpose “hardwired” circuitry, or in a combination of suchforms. Such special-purpose circuitry (if any) can be in the form of,for example, one or more application-specific integrated circuits(ASICS), programmable logic devices (PLDs), field-programmable gatearrays (FPGAs), etc.

Software or firmware implementing the techniques introduced herein maybe stored on a machine-readable storage medium (also generally referredto herein as computer-readable storage medium or computer-readablemedium) and may be executed by one or more general-purpose orspecial-purpose programmable microprocessors. A “machine-readablemedium”, as the term is used herein, includes any mechanism that canstore information in a form accessible by a machine (a machine may be,for example, a computer, network device, cellular phone, personaldigital assistant (PDA), manufacturing took, any device with one or moreprocessors, etc.). For example, a machine-accessible medium includesrecordable/non-recordable media (e.g., read-only memory (ROM); randomaccess memory (RAM); magnetic disk storage media; optical storage media;flash memory devices; etc.), etc. The following examples are put forthso as to provide those of ordinary skill in the art with a completedisclosure and description of how to make and use the embodiments of theinvention, and are not intended to limit the scope of what the inventorsregard as their invention nor are they intended to represent that theexperiments below are all or the only experiments performed. Effortshave been made to ensure accuracy with respect to numbers used (e.g.,amounts, temperature, etc.) but some experimental errors and deviationsshould be accounted for. Unless indicated otherwise, parts are parts byweight, molecular weight is weight average molecular weight, temperatureis in degrees Centigrade, and pressure is at or near atmospheric.

1-27. (canceled)
 28. A glucose monitoring system, comprising: an on bodyunit comprising: a housing configured to be positioned on a skin of asubject; a glucose sensor, at least a portion of which is configured tobe positioned under the skin of the subject and in contact with a bodilyfluid; and sensor electronics coupled with the glucose sensor anddisposed within the housing, the sensor electronics comprising acommunication module, a processor, and memory for storing instructions,wherein the processor is communicatively coupled with an accelerometer,wherein the glucose sensor and the sensor electronics are coupled viaconductive contacts prior to positioning the housing on the skin of thesubject, and wherein the instructions, when executed by the processor,cause the processor to: generate data indicative of a glucose levelbased on one or more samples obtained by the glucose sensor, receiveinput information from the accelerometer, and adjust a variable datasetting based on the received input information from the accelerometer.29. The glucose monitoring system of claim 28, wherein the variable datasetting comprises a frequency at which the data indicative of theglucose level is stored in the memory.
 30. The glucose monitoring systemof claim 28, wherein the variable data setting comprises a duration forwhich the data indicative of the glucose level is stored in the memory.31. The glucose monitoring system of claim 28, wherein the variable datasetting comprises a frequency at which the data indicative of theglucose level is logged to a rolling log.
 32. The glucose monitoringsystem of claim 28, wherein the variable data setting comprises afrequency at which the glucose sensor samples a glucose level.
 33. Theglucose monitoring system of claim 28, wherein the variable data settingcomprises a frequency at which the data indicative of the glucose levelis monitored.
 34. The glucose monitoring system of claim 28, wherein thevariable data setting comprises a rate at which the data indicative ofthe glucose level is transmitted to a reader device.
 35. The glucosemonitoring system of claim 28, wherein the input information from theaccelerometer comprises sleep information associated with the subject.36. The glucose monitoring system of claim 28, wherein the inputinformation from the accelerometer comprises exercise informationassociated with the subject.
 37. The glucose monitoring system of claim28, wherein the variable data setting is increased during exercise basedon the received input information from the accelerometer.
 38. Theglucose monitoring system of claim 28, wherein the variable data settingis decreased during sleep based on the received input information fromthe accelerometer.
 39. The glucose monitoring system of claim 28,wherein the variable data setting is decreased during a period of lowglucose variability based at least in part on the received inputinformation from the accelerometer.
 40. The glucose monitoring system ofclaim 28, wherein the instructions, when executed by the processor,further cause the processor to adjust the variable data setting in realtime.
 41. The glucose monitoring system of claim 28, wherein theinstructions, when executed by the processors, further cause theprocessor to adjust the variable data setting retrospectively.
 42. Theglucose monitoring system of claim 28, wherein the variable data settingis set to every minute.
 43. The glucose monitoring system of claim 28,wherein the housing is a single integral unit configured to rest on theskin of the subject.
 44. The glucose monitoring system of claim 28,wherein the communication module of the sensor electronics is configuredto wirelessly transmit the data indicative of the glucose level to areader device.
 45. The glucose monitoring system of claim 44, whereinthe communication module of the sensor electronics is further configuredto transmit the data indicative of the glucose level according to aBluetooth communication protocol.
 46. The glucose monitoring system ofclaim 44, wherein the reader device comprises a smartphone.
 47. Theglucose monitoring system of claim 28, wherein a portion of the glucosesensor is configured to be in fluid contact with interstitial fluid ofthe subject.
 48. The glucose monitoring system of claim 28, wherein theprocessor is further configured to cause an alarm to activate if aglucose level exceeds a threshold.
 49. The glucose monitoring system ofclaim 28, further comprising a temperature probe coupled with the sensorelectronics.
 50. The glucose monitoring system of claim 28, wherein theglucose sensor comprises one or more working electrodes and a counterelectrode.
 51. The system of claim 28, further comprising a referencevoltage generator.